856465307880 has 256 divisors, whose sum is σ = 3185089689600. Its totient is φ = 179404416000.

The previous prime is 856465307857. The next prime is 856465307903. The reversal of 856465307880 is 88703564658.

It is an interprime number because it is at equal distance from previous prime (856465307857) and next prime (856465307903).

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1235755 + ... + 1800005.

It is an arithmetic number, because the mean of its divisors is an integer number (12441756600).

Almost surely, 2^856465307880 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 856465307880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1592544844800).

856465307880 is an abundant number, since it is smaller than the sum of its proper divisors (2328624381720).

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

856465307880 is a wasteful number, since it uses less digits than its factorization.

856465307880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 564424 (or 564420 counting only the distinct ones).

The product of its (nonzero) digits is 38707200, while the sum is 60.

The spelling of 856465307880 in words is "eight hundred fifty-six billion, four hundred sixty-five million, three hundred seven thousand, eight hundred eighty".