21213974128 has 40 divisors (see below), whose sum is σ = 41707375200. Its totient is φ = 10450970880.

The previous prime is 21213974113. The next prime is 21213974129. The reversal of 21213974128 is 82147931212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213974129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2127298 + ... + 2137246.

It is an arithmetic number, because the mean of its divisors is an integer number (1042684380).

Almost surely, 2^21213974128 is an apocalyptic number.

It is an amenable number.

21213974128 is a deficient number, since it is larger than the sum of its proper divisors (20493401072).

21213974128 is a wasteful number, since it uses less digits than its factorization.

21213974128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11905 (or 11899 counting only the distinct ones).

The product of its digits is 48384, while the sum is 40.

The spelling of 21213974128 in words is "twenty-one billion, two hundred thirteen million, nine hundred seventy-four thousand, one hundred twenty-eight".