21094972 has 6 divisors (see below), whose sum is σ = 36916208. Its totient is φ = 10547484.

The previous prime is 21094937. The next prime is 21094999. The reversal of 21094972 is 27949012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2636868 + ... + 2636875.

Almost surely, 2^21094972 is an apocalyptic number.

It is an amenable number.

21094972 is a deficient number, since it is larger than the sum of its proper divisors (15821236).

21094972 is a wasteful number, since it uses less digits than its factorization.

21094972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5273747 (or 5273745 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 21094972 is about 4592.9263003014. The cubic root of 21094972 is about 276.3076978642.

The spelling of 21094972 in words is "twenty-one million, ninety-four thousand, nine hundred seventy-two".