19523977965913 has 2 divisors, whose sum is σ = 19523977965914. Its totient is φ = 19523977965912.

The previous prime is 19523977965871. The next prime is 19523977965917. The reversal of 19523977965913 is 31956977932591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19425060167769 + 98917798144 = 4407387^2 + 314512^2 .

It is a cyclic number.

It is not a de Polignac number, because 19523977965913 - 2¹⁷ = 19523977834841 is a prime.

It is a super-2 number, since 2×19523977965913² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19523977965913.

It is not a weakly prime, because it can be changed into another prime (19523977965917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9761988982956 + 9761988982957.

It is an arithmetic number, because the mean of its divisors is an integer number (9761988982957).

Almost surely, 2^{19523977965913} is an apocalyptic number.

It is an amenable number.

19523977965913 is a deficient number, since it is larger than the sum of its proper divisors (1).

19523977965913 is an equidigital number, since it uses as much as digits as its factorization.

19523977965913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 868020300, while the sum is 76.

The spelling of 19523977965913 in words is "nineteen trillion, five hundred twenty-three billion, nine hundred seventy-seven million, nine hundred sixty-five thousand, nine hundred thirteen".