861407138433440 has 48 divisors (see below), whose sum is σ = 2100721924707840. Its totient is φ = 333447924552960.

The previous prime is 861407138433419. The next prime is 861407138433451. The reversal of 861407138433440 is 44334831704168.

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, 86835392060 + ... + 86835401979.

It is an arithmetic number, because the mean of its divisors is an integer number (43765040098080).

Almost surely, 2^{861407138433440} is an apocalyptic number.

861407138433440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

861407138433440 is an abundant number, since it is smaller than the sum of its proper divisors (1239314786274400).

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

861407138433440 is a wasteful number, since it uses less digits than its factorization.

861407138433440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173670794085 (or 173670794077 counting only the distinct ones).

The product of its (nonzero) digits is 18579456, while the sum is 56.

The spelling of 861407138433440 in words is "eight hundred sixty-one trillion, four hundred seven billion, one hundred thirty-eight million, four hundred thirty-three thousand, four hundred forty".