19972489169 has 2 divisors, whose sum is σ = 19972489170. Its totient is φ = 19972489168.

The previous prime is 19972489079. The next prime is 19972489181. The reversal of 19972489169 is 96198427991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12157929169 + 7814560000 = 110263^2 + 88400^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19972489169 is a prime.

It is a super-2 number, since 2×19972489169² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19972489769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9986244584 + 9986244585.

It is an arithmetic number, because the mean of its divisors is an integer number (9986244585).

Almost surely, 2^19972489169 is an apocalyptic number.

It is an amenable number.

19972489169 is a deficient number, since it is larger than the sum of its proper divisors (1).

19972489169 is an equidigital number, since it uses as much as digits as its factorization.

19972489169 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17635968, while the sum is 65.

The spelling of 19972489169 in words is "nineteen billion, nine hundred seventy-two million, four hundred eighty-nine thousand, one hundred sixty-nine".