21238174464 has 144 divisors (see below), whose sum is σ = 64076947200. Its totient is φ = 6190829568.

The previous prime is 21238174459. The next prime is 21238174471. The reversal of 21238174464 is 46447183212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 133717 + ... + 245675.

It is an arithmetic number, because the mean of its divisors is an integer number (444978800).

Almost surely, 2^21238174464 is an apocalyptic number.

21238174464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21238174464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32038473600).

21238174464 is an abundant number, since it is smaller than the sum of its proper divisors (42838772736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21238174464 is a wasteful number, since it uses less digits than its factorization.

21238174464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112010 (or 111996 counting only the distinct ones).

The product of its digits is 258048, while the sum is 42.

The spelling of 21238174464 in words is "twenty-one billion, two hundred thirty-eight million, one hundred seventy-four thousand, four hundred sixty-four".