27840400 has 120 divisors (see below), whose sum is σ = 78171584. Its totient is φ = 9331200.

The previous prime is 27840367. The next prime is 27840413. The reversal of 27840400 is 404872.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 170719 + ... + 170881.

Almost surely, 2^27840400 is an apocalyptic number.

27840400 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 27840400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39085792).

27840400 is an abundant number, since it is smaller than the sum of its proper divisors (50331184).

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

27840400 is a wasteful number, since it uses less digits than its factorization.

27840400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 238 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 27840400 is about 5276.4002880752. The cubic root of 27840400 is about 303.0808455897.

Subtracting from 27840400 its reverse (404872), we obtain a triangular number (27435528 = T₇₄₀₇).

The spelling of 27840400 in words is "twenty-seven million, eight hundred forty thousand, four hundred".