21213612523264 has 144 divisors (see below), whose sum is σ = 51244302606336. Its totient is φ = 8556071731200.

The previous prime is 21213612523261. The next prime is 21213612523303. The reversal of 21213612523264 is 46232521631212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213612523261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 590709469 + ... + 590745379.

It is an arithmetic number, because the mean of its divisors is an integer number (355863212544).

Almost surely, 2^{21213612523264} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21213612523264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25622151303168).

21213612523264 is an abundant number, since it is smaller than the sum of its proper divisors (30030690083072).

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

21213612523264 is a wasteful number, since it uses less digits than its factorization.

21213612523264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55342 (or 55328 counting only the distinct ones).

The product of its digits is 207360, while the sum is 40.

The spelling of 21213612523264 in words is "twenty-one trillion, two hundred thirteen billion, six hundred twelve million, five hundred twenty-three thousand, two hundred sixty-four".