85815918720 has 768 divisors, whose sum is σ = 361928476800. Its totient is φ = 19150774272.

The previous prime is 85815918709. The next prime is 85815918737. The reversal of 85815918720 is 2781951858.

85815918720 is a `hidden beast` number, since 8 + 581 + 59 + 1 + 8 + 7 + 2 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 36407782 + ... + 36410138.

Almost surely, 2^85815918720 is an apocalyptic number.

85815918720 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 85815918720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180964238400).

85815918720 is an abundant number, since it is smaller than the sum of its proper divisors (276112558080).

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

85815918720 is a wasteful number, since it uses less digits than its factorization.

85815918720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2442 (or 2417 counting only the distinct ones).

The product of its (nonzero) digits is 1612800, while the sum is 54.

The spelling of 85815918720 in words is "eighty-five billion, eight hundred fifteen million, nine hundred eighteen thousand, seven hundred twenty".