21586770978696 has 672 divisors, whose sum is σ = 81063718682400. Its totient is φ = 5311835988480.

The previous prime is 21586770978683. The next prime is 21586770978701. The reversal of 21586770978696 is 69687907768512.

21586770978696 is a `hidden beast` number, since 21 + 586 + 7 + 7 + 0 + 9 + 7 + 8 + 6 + 9 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 167 ways as a sum of consecutive naturals, for example, 59544796 + ... + 59906228.

Almost surely, 2^{21586770978696} 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 21586770978696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40531859341200).

21586770978696 is an abundant number, since it is smaller than the sum of its proper divisors (59476947703704).

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

21586770978696 is a wasteful number, since it uses less digits than its factorization.

21586770978696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361501 (or 361475 counting only the distinct ones).

The product of its (nonzero) digits is 3840721920, while the sum is 81.

The spelling of 21586770978696 in words is "twenty-one trillion, five hundred eighty-six billion, seven hundred seventy million, nine hundred seventy-eight thousand, six hundred ninety-six".