19956277889969 has 2 divisors, whose sum is σ = 19956277889970. Its totient is φ = 19956277889968.

The previous prime is 19956277889957. The next prime is 19956277890037. The reversal of 19956277889969 is 96998877265991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18862343886400 + 1093934003569 = 4343080^2 + 1045913^2 .

It is an emirp because it is prime and its reverse (96998877265991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19956277889969 is a prime.

It is a super-2 number, since 2×19956277889969² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19956277889869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9978138944984 + 9978138944985.

It is an arithmetic number, because the mean of its divisors is an integer number (9978138944985).

Almost surely, 2^{19956277889969} is an apocalyptic number.

It is an amenable number.

19956277889969 is a deficient number, since it is larger than the sum of its proper divisors (1).

19956277889969 is an equidigital number, since it uses as much as digits as its factorization.

19956277889969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 66663959040, while the sum is 95.

The spelling of 19956277889969 in words is "nineteen trillion, nine hundred fifty-six billion, two hundred seventy-seven million, eight hundred eighty-nine thousand, nine hundred sixty-nine".