216464400 has 360 divisors, whose sum is σ = 831134304. Its totient is φ = 53913600.

The previous prime is 216464377. The next prime is 216464407. The reversal of 216464400 is 4464612.

216464400 is a `hidden beast` number, since 2 + 16 + 4 + 644 + 0 + 0 = 666.

216464400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216464407) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1652335 + ... + 1652465.

Almost surely, 2^216464400 is an apocalyptic number.

216464400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216464400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (415567152).

216464400 is an abundant number, since it is smaller than the sum of its proper divisors (614669904).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

216464400 is a wasteful number, since it uses less digits than its factorization.

216464400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181 (or 158 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 216464400 is about 14712.7291825820. The cubic root of 216464400 is about 600.4296922009.

It can be divided in two parts, 2164 and 64400, that added together give a square (66564 = 258²).

The spelling of 216464400 in words is "two hundred sixteen million, four hundred sixty-four thousand, four hundred".