21020706776916 has 864 divisors, whose sum is σ = 71352657492480. Its totient is φ = 5089796997120.

The previous prime is 21020706776903. The next prime is 21020706776929. The reversal of 21020706776916 is 61967760702012.

It is an interprime number because it is at equal distance from previous prime (21020706776903) and next prime (21020706776929).

It is a super-2 number, since 2×21020706776916² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 32489500105 + ... + 32489500751.

It is an arithmetic number, because the mean of its divisors is an integer number (82584094320).

Almost surely, 2^{21020706776916} 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 21020706776916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35676328746240).

21020706776916 is an abundant number, since it is smaller than the sum of its proper divisors (50331950715564).

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

21020706776916 is a wasteful number, since it uses less digits than its factorization.

21020706776916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1205 (or 1189 counting only the distinct ones).

The product of its (nonzero) digits is 2667168, while the sum is 54.

The spelling of 21020706776916 in words is "twenty-one trillion, twenty billion, seven hundred six million, seven hundred seventy-six thousand, nine hundred sixteen".