21990362712 has 128 divisors (see below), whose sum is σ = 57514406400. Its totient is φ = 7000261632.

The previous prime is 21990362623. The next prime is 21990362729. The reversal of 21990362712 is 21726309912.

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, 22370173 + ... + 22371155.

It is an arithmetic number, because the mean of its divisors is an integer number (449331300).

Almost surely, 2^21990362712 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 21990362712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28757203200).

21990362712 is an abundant number, since it is smaller than the sum of its proper divisors (35524043688).

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

21990362712 is a wasteful number, since it uses less digits than its factorization.

21990362712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1497 (or 1493 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 42.

The spelling of 21990362712 in words is "twenty-one billion, nine hundred ninety million, three hundred sixty-two thousand, seven hundred twelve".