20610561600 has 504 divisors, whose sum is σ = 78270079680. Its totient is φ = 5128704000.

The previous prime is 20610561583. The next prime is 20610561623. The reversal of 20610561600 is 616501602.

It is a happy number.

20610561600 is a `hidden beast` number, since 2 + 0 + 6 + 1 + 0 + 56 + 1 + 600 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 19425070 + ... + 19426130.

Almost surely, 2^20610561600 is an apocalyptic number.

20610561600 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 20610561600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39135039840).

20610561600 is an abundant number, since it is smaller than the sum of its proper divisors (57659518080).

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

20610561600 is a wasteful number, since it uses less digits than its factorization.

20610561600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1179 (or 1161 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The spelling of 20610561600 in words is "twenty billion, six hundred ten million, five hundred sixty-one thousand, six hundred".