861513997032 has 320 divisors, whose sum is σ = 2707991470800. Its totient is φ = 254062448640.

The previous prime is 861513996971. The next prime is 861513997063. The reversal of 861513997032 is 230799315168.

861513997032 is a `hidden beast` number, since 8 + 6 + 1 + 513 + 9 + 97 + 0 + 32 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 404259442596 + 457254554436 = 635814^2 + 676206^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 861513997032.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 33455682 + ... + 33481422.

Almost surely, 2^861513997032 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 861513997032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1353995735400).

861513997032 is an abundant number, since it is smaller than the sum of its proper divisors (1846477473768).

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

861513997032 is a wasteful number, since it uses less digits than its factorization.

861513997032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25938 (or 25925 counting only the distinct ones).

The product of its (nonzero) digits is 2449440, while the sum is 54.

The spelling of 861513997032 in words is "eight hundred sixty-one billion, five hundred thirteen million, nine hundred ninety-seven thousand, thirty-two".