21180308672 has 56 divisors (see below), whose sum is σ = 44513601600. Its totient is φ = 9971133696.

The previous prime is 21180308663. The next prime is 21180308689. The reversal of 21180308672 is 27680308112.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 144779 + ... + 251637.

Almost surely, 2^21180308672 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 21180308672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22256800800).

21180308672 is an abundant number, since it is smaller than the sum of its proper divisors (23333292928).

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

21180308672 is a wasteful number, since it uses less digits than its factorization.

21180308672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107053 (or 107043 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 38.

The spelling of 21180308672 in words is "twenty-one billion, one hundred eighty million, three hundred eight thousand, six hundred seventy-two".