21272974 has 4 divisors (see below), whose sum is σ = 31909464. Its totient is φ = 10636486.

The previous prime is 21272971. The next prime is 21272987. The reversal of 21272974 is 47927212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21272971) by changing a digit.

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, 5318242 + ... + 5318245.

It is an arithmetic number, because the mean of its divisors is an integer number (7977366).

Almost surely, 2^21272974 is an apocalyptic number.

21272974 is a deficient number, since it is larger than the sum of its proper divisors (10636490).

21272974 is a wasteful number, since it uses less digits than its factorization.

21272974 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10636489.

The product of its digits is 14112, while the sum is 34.

The square root of 21272974 is about 4612.2634356680. The cubic root of 21272974 is about 277.0826950118.

The spelling of 21272974 in words is "twenty-one million, two hundred seventy-two thousand, nine hundred seventy-four".