21973698 has 12 divisors (see below), whose sum is σ = 47609718. Its totient is φ = 7324560.

The previous prime is 21973697. The next prime is 21973729. The reversal of 21973698 is 89637912.

It can be written as a sum of positive squares in only one way, i.e., 17164449 + 4809249 = 4143^2 + 2193^2 .

It is not an unprimeable number, because it can be changed into a prime (21973691) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 610363 + ... + 610398.

Almost surely, 2^21973698 is an apocalyptic number.

21973698 is an abundant number, since it is smaller than the sum of its proper divisors (25636020).

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

21973698 is a wasteful number, since it uses less digits than its factorization.

21973698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220769 (or 1220766 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 21973698 is about 4687.6111186829. The cubic root of 21973698 is about 280.0922230227.

The spelling of 21973698 in words is "twenty-one million, nine hundred seventy-three thousand, six hundred ninety-eight".