21989210392 has 8 divisors (see below), whose sum is σ = 41229769500. Its totient is φ = 10994605192.

The previous prime is 21989210351. The next prime is 21989210393. The reversal of 21989210392 is 29301298912.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21989210393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1374325642 + ... + 1374325657.

Almost surely, 2^21989210392 is an apocalyptic number.

It is an amenable number.

21989210392 is a deficient number, since it is larger than the sum of its proper divisors (19240559108).

21989210392 is a wasteful number, since it uses less digits than its factorization.

21989210392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2748651305 (or 2748651301 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 46.

The spelling of 21989210392 in words is "twenty-one billion, nine hundred eighty-nine million, two hundred ten thousand, three hundred ninety-two".