12511564997 has 2 divisors, whose sum is σ = 12511564998. Its totient is φ = 12511564996.

The previous prime is 12511564993. The next prime is 12511565023. The reversal of 12511564997 is 79946511521.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6260132641 + 6251432356 = 79121^2 + 79066^2 .

It is a cyclic number.

It is not a de Polignac number, because 12511564997 - 2² = 12511564993 is a prime.

It is a super-2 number, since 2×12511564997² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12511564993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6255782498 + 6255782499.

It is an arithmetic number, because the mean of its divisors is an integer number (6255782499).

Almost surely, 2^12511564997 is an apocalyptic number.

It is an amenable number.

12511564997 is a deficient number, since it is larger than the sum of its proper divisors (1).

12511564997 is an equidigital number, since it uses as much as digits as its factorization.

12511564997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 680400, while the sum is 50.

The spelling of 12511564997 in words is "twelve billion, five hundred eleven million, five hundred sixty-four thousand, nine hundred ninety-seven".