21021631699416 has 128 divisors (see below), whose sum is σ = 55738758398400. Its totient is φ = 6595061760000.

The previous prime is 21021631699361. The next prime is 21021631699427. The reversal of 21021631699416 is 61499613612012.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 33965046 + ... + 34578426.

Almost surely, 2^{21021631699416} 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 21021631699416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27869379199200).

21021631699416 is an abundant number, since it is smaller than the sum of its proper divisors (34717126698984).

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

21021631699416 is a wasteful number, since it uses less digits than its factorization.

21021631699416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 614661 (or 614657 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 51.

The spelling of 21021631699416 in words is "twenty-one trillion, twenty-one billion, six hundred thirty-one million, six hundred ninety-nine thousand, four hundred sixteen".