21212974 has 16 divisors (see below), whose sum is σ = 34101648. Its totient is φ = 9860992.

The previous prime is 21212941. The next prime is 21212977. The reversal of 21212974 is 47921212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212977) 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, 937 + ... + 6580.

It is an arithmetic number, because the mean of its divisors is an integer number (2131353).

Almost surely, 2^21212974 is an apocalyptic number.

21212974 is a deficient number, since it is larger than the sum of its proper divisors (12888674).

21212974 is a wasteful number, since it uses less digits than its factorization.

21212974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7619.

The product of its digits is 2016, while the sum is 28.

The square root of 21212974 is about 4605.7544441709. The cubic root of 21212974 is about 276.8219476371.

The spelling of 21212974 in words is "twenty-one million, two hundred twelve thousand, nine hundred seventy-four".