21980692 has 6 divisors (see below), whose sum is σ = 38466218. Its totient is φ = 10990344.

The previous prime is 21980687. The next prime is 21980719. The reversal of 21980692 is 29608912.

It can be written as a sum of positive squares in only one way, i.e., 21123216 + 857476 = 4596^2 + 926^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2747583 + ... + 2747590.

Almost surely, 2^21980692 is an apocalyptic number.

It is an amenable number.

21980692 is a deficient number, since it is larger than the sum of its proper divisors (16485526).

21980692 is a wasteful number, since it uses less digits than its factorization.

21980692 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5495177 (or 5495175 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 21980692 is about 4688.3570683130. The cubic root of 21980692 is about 280.1219366862.

The spelling of 21980692 in words is "twenty-one million, nine hundred eighty thousand, six hundred ninety-two".