861390810000 has 600 divisors, whose sum is σ = 3452201941760. Its totient is φ = 196349184000.

The previous prime is 861390809971. The next prime is 861390810031. The reversal of 861390810000 is 18093168.

It is a tau number, because it is divible by the number of its divisors (600).

It is a super-2 number, since 2×861390810000² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 257668329 + ... + 257671671.

Almost surely, 2^861390810000 is an apocalyptic number.

861390810000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861390810000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1726100970880).

861390810000 is an abundant number, since it is smaller than the sum of its proper divisors (2590811131760).

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

861390810000 is a wasteful number, since it uses less digits than its factorization.

861390810000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3793 (or 3769 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The spelling of 861390810000 in words is "eight hundred sixty-one billion, three hundred ninety million, eight hundred ten thousand".