21136664120 has 128 divisors (see below), whose sum is σ = 55929968640. Its totient is φ = 7087434240.

The previous prime is 21136664089. The next prime is 21136664137. The reversal of 21136664120 is 2146663112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10426547 + ... + 10428573.

It is an arithmetic number, because the mean of its divisors is an integer number (436952880).

Almost surely, 2^21136664120 is an apocalyptic number.

21136664120 is a gapful number since it is divisible by the number (20) 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 21136664120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27964984320).

21136664120 is an abundant number, since it is smaller than the sum of its proper divisors (34793304520).

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

21136664120 is a wasteful number, since it uses less digits than its factorization.

21136664120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3885 (or 3881 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 32.

The spelling of 21136664120 in words is "twenty-one billion, one hundred thirty-six million, six hundred sixty-four thousand, one hundred twenty".