21112377672 has 128 divisors (see below), whose sum is σ = 56773509120. Its totient is φ = 6527136000.

The previous prime is 21112377659. The next prime is 21112377701. The reversal of 21112377672 is 27677321112.

It is a self number, because there is not a number n which added to its sum of digits gives 21112377672.

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, 2386297 + ... + 2395127.

It is an arithmetic number, because the mean of its divisors is an integer number (443543040).

Almost surely, 2^21112377672 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 21112377672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28386754560).

21112377672 is an abundant number, since it is smaller than the sum of its proper divisors (35661131448).

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

21112377672 is a wasteful number, since it uses less digits than its factorization.

21112377672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8995 (or 8991 counting only the distinct ones).

The product of its digits is 49392, while the sum is 39.

Adding to 21112377672 its reverse (27677321112), we get a palindrome (48789698784).

The spelling of 21112377672 in words is "twenty-one billion, one hundred twelve million, three hundred seventy-seven thousand, six hundred seventy-two".