861540008540 has 24 divisors (see below), whose sum is σ = 1853361678672. Its totient is φ = 336210734720.

The previous prime is 861540008491. The next prime is 861540008657. The reversal of 861540008540 is 45800045168.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a congruent number.

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, 525328454 + ... + 525330093.

It is an arithmetic number, because the mean of its divisors is an integer number (77223403278).

Almost surely, 2^861540008540 is an apocalyptic number.

It is an amenable number.

861540008540 is an abundant number, since it is smaller than the sum of its proper divisors (991821670132).

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

861540008540 is a wasteful number, since it uses less digits than its factorization.

861540008540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1050658597 (or 1050658595 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 41.

The spelling of 861540008540 in words is "eight hundred sixty-one billion, five hundred forty million, eight thousand, five hundred forty".