21969562608 has 400 divisors, whose sum is σ = 75591352320. Its totient is φ = 6027955200.

The previous prime is 21969562561. The next prime is 21969562613. The reversal of 21969562608 is 80626596912.

It is a happy number.

21969562608 is a `hidden beast` number, since 2 + 1 + 9 + 6 + 9 + 5 + 626 + 0 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 53715108 + ... + 53715516.

Almost surely, 2^21969562608 is an apocalyptic number.

21969562608 is a gapful number since it is divisible by the number (28) 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 21969562608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37795676160).

21969562608 is an abundant number, since it is smaller than the sum of its proper divisors (53621789712).

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

21969562608 is a wasteful number, since it uses less digits than its factorization.

21969562608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658 (or 643 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The spelling of 21969562608 in words is "twenty-one billion, nine hundred sixty-nine million, five hundred sixty-two thousand, six hundred eight".