78264840 has 32 divisors (see below), whose sum is σ = 234794880. Its totient is φ = 20870592.

The previous prime is 78264827. The next prime is 78264853. The reversal of 78264840 is 4846287.

It is an interprime number because it is at equal distance from previous prime (78264827) and next prime (78264853).

It is a super-2 number, since 2×78264840² = 12250770360451200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 325984 + ... + 326223.

It is an arithmetic number, because the mean of its divisors is an integer number (7337340).

Almost surely, 2^78264840 is an apocalyptic number.

It is an amenable number.

78264840 is an abundant number, since it is smaller than the sum of its proper divisors (156530040).

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

78264840 is a wasteful number, since it uses less digits than its factorization.

78264840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 652221 (or 652217 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 39.

The square root of 78264840 is about 8846.7417731049. The cubic root of 78264840 is about 427.7488992080.

The spelling of 78264840 in words is "seventy-eight million, two hundred sixty-four thousand, eight hundred forty".