861515264 has 40 divisors (see below), whose sum is σ = 1758021408. Its totient is φ = 421580800.

The previous prime is 861515243. The next prime is 861515269. The reversal of 861515264 is 462515168.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861515269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6164 + ... + 41964.

Almost surely, 2^861515264 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 861515264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (879010704).

861515264 is an abundant number, since it is smaller than the sum of its proper divisors (896506144).

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

861515264 is an equidigital number, since it uses as much as digits as its factorization.

861515264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35866 (or 35850 counting only the distinct ones).

The product of its digits is 57600, while the sum is 38.

The square root of 861515264 is about 29351.5802641016. The cubic root of 861515264 is about 951.5267284863.

The spelling of 861515264 in words is "eight hundred sixty-one million, five hundred fifteen thousand, two hundred sixty-four".