12621399552 has 240 divisors, whose sum is σ = 37634680512. Its totient is φ = 4069785600.

The previous prime is 12621399521. The next prime is 12621399577. The reversal of 12621399552 is 25599312621.

12621399552 is a `hidden beast` number, since 1 + 2 + 6 + 2 + 1 + 3 + 99 + 552 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 12621399498 and 12621399507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21873888 + ... + 21874464.

Almost surely, 2^12621399552 is an apocalyptic number.

12621399552 is a gapful number since it is divisible by the number (12) 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 12621399552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18817340256).

12621399552 is an abundant number, since it is smaller than the sum of its proper divisors (25013280960).

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

12621399552 is a wasteful number, since it uses less digits than its factorization.

12621399552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 749 (or 730 counting only the distinct ones).

The product of its digits is 291600, while the sum is 45.

The spelling of 12621399552 in words is "twelve billion, six hundred twenty-one million, three hundred ninety-nine thousand, five hundred fifty-two".