21653300131236 has 18 divisors (see below), whose sum is σ = 54734730887382. Its totient is φ = 7217766710400.

The previous prime is 21653300131231. The next prime is 21653300131249. The reversal of 21653300131236 is 63213100335612.

21653300131236 is a `hidden beast` number, since 2 + 1 + 6 + 5 + 3 + 300 + 1 + 312 + 36 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15760058371236 + 5893241760000 = 3969894^2 + 2427600^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 601480559201 = 21653300131236 / (2 + 1 + 6 + 5 + 3 + 3 + 0 + 0 + 1 + 3 + 1 + 2 + 3 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 21653300131236.

It is not an unprimeable number, because it can be changed into a prime (21653300131231) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 300740279565 + ... + 300740279636.

Almost surely, 2^{21653300131236} is an apocalyptic number.

It is an amenable number.

21653300131236 is an abundant number, since it is smaller than the sum of its proper divisors (33081430756146).

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

21653300131236 is a wasteful number, since it uses less digits than its factorization.

21653300131236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601480559211 (or 601480559206 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 36.

Adding to 21653300131236 its reverse (63213100335612), we get a palindrome (84866400466848).

The spelling of 21653300131236 in words is "twenty-one trillion, six hundred fifty-three billion, three hundred million, one hundred thirty-one thousand, two hundred thirty-six".