21012311099953 has 2 divisors, whose sum is σ = 21012311099954. Its totient is φ = 21012311099952.

The previous prime is 21012311099933. The next prime is 21012311100031. The reversal of 21012311099953 is 35999011321012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20463753121344 + 548557978609 = 4523688^2 + 740647^2 .

It is a cyclic number.

It is not a de Polignac number, because 21012311099953 - 2²⁹ = 21011774229041 is a prime.

It is a super-2 number, since 2×21012311099953² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21012311099933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506155549976 + 10506155549977.

It is an arithmetic number, because the mean of its divisors is an integer number (10506155549977).

Almost surely, 2^{21012311099953} is an apocalyptic number.

It is an amenable number.

21012311099953 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012311099953 is an equidigital number, since it uses as much as digits as its factorization.

21012311099953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 131220, while the sum is 46.

The spelling of 21012311099953 in words is "twenty-one trillion, twelve billion, three hundred eleven million, ninety-nine thousand, nine hundred fifty-three".