864255840 has 96 divisors (see below), whose sum is σ = 3111333120. Its totient is φ = 197543424.

The previous prime is 864255823. The next prime is 864255853. The reversal of 864255840 is 48552468.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 864255792 and 864255801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 125250 + ... + 131969.

It is an arithmetic number, because the mean of its divisors is an integer number (32409720).

Almost surely, 2^864255840 is an apocalyptic number.

864255840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

864255840 is an abundant number, since it is smaller than the sum of its proper divisors (2247077280).

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

864255840 is a wasteful number, since it uses less digits than its factorization.

864255840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257244 (or 257236 counting only the distinct ones).

The product of its (nonzero) digits is 307200, while the sum is 42.

The square root of 864255840 is about 29398.2285180587. The cubic root of 864255840 is about 952.5346313212.

The spelling of 864255840 in words is "eight hundred sixty-four million, two hundred fifty-five thousand, eight hundred forty".