264644820 has 120 divisors (see below), whose sum is σ = 905734368. Its totient is φ = 64152000.

The previous prime is 264644803. The next prime is 264644843. The reversal of 264644820 is 28446462.

It is a happy number.

264644820 is a `hidden beast` number, since 2 + 6 + 4 + 644 + 8 + 2 + 0 = 666.

264644820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 10395 + ... + 25245.

Almost surely, 2^264644820 is an apocalyptic number.

264644820 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 264644820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (452867184).

264644820 is an abundant number, since it is smaller than the sum of its proper divisors (641089548).

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

264644820 is a wasteful number, since it uses less digits than its factorization.

264644820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14883 (or 14872 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 36.

The square root of 264644820 is about 16267.9076712403. The cubic root of 264644820 is about 642.0287348480.

The spelling of 264644820 in words is "two hundred sixty-four million, six hundred forty-four thousand, eight hundred twenty".