21252973 has 8 divisors (see below), whose sum is σ = 24318848. Its totient is φ = 18194544.

The previous prime is 21252971. The next prime is 21252983. The reversal of 21252973 is 37925212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21252973 - 2¹ = 21252971 is a prime.

It is a super-2 number, since 2×21252973² = 903377722677458, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21252971) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7240 + ... + 9742.

It is an arithmetic number, because the mean of its divisors is an integer number (3039856).

Almost surely, 2^21252973 is an apocalyptic number.

It is an amenable number.

21252973 is a deficient number, since it is larger than the sum of its proper divisors (3065875).

21252973 is a wasteful number, since it uses less digits than its factorization.

21252973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3723.

The product of its digits is 7560, while the sum is 31.

The square root of 21252973 is about 4610.0946844940. The cubic root of 21252973 is about 276.9958294150.

The spelling of 21252973 in words is "twenty-one million, two hundred fifty-two thousand, nine hundred seventy-three".