865420881 has 16 divisors (see below), whose sum is σ = 1271557056. Its totient is φ = 520180416.

The previous prime is 865420877. The next prime is 865420883. The reversal of 865420881 is 188024568.

It is not a de Polignac number, because 865420881 - 2² = 865420877 is a prime.

It is a super-2 number, since 2×865420881² = 1497906602541632322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (865420883) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 256350 + ... + 259703.

It is an arithmetic number, because the mean of its divisors is an integer number (79472316).

Almost surely, 2^865420881 is an apocalyptic number.

It is an amenable number.

865420881 is a deficient number, since it is larger than the sum of its proper divisors (406136175).

865420881 is a wasteful number, since it uses less digits than its factorization.

865420881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 516112.

The product of its (nonzero) digits is 122880, while the sum is 42.

The square root of 865420881 is about 29418.0366612050. The cubic root of 865420881 is about 952.9624535651.

The spelling of 865420881 in words is "eight hundred sixty-five million, four hundred twenty thousand, eight hundred eighty-one".