19957969 has 2 divisors, whose sum is σ = 19957970. Its totient is φ = 19957968.

The previous prime is 19957967. The next prime is 19957979. The reversal of 19957969 is 96975991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10316944 + 9641025 = 3212^2 + 3105^2 .

It is a cyclic number.

It is not a de Polignac number, because 19957969 - 2¹ = 19957967 is a prime.

It is a super-2 number, since 2×19957969² = 796641053209922, which contains 22 as substring.

Together with 19957967, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (19957967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9978984 + 9978985.

It is an arithmetic number, because the mean of its divisors is an integer number (9978985).

Almost surely, 2^19957969 is an apocalyptic number.

It is an amenable number.

19957969 is a deficient number, since it is larger than the sum of its proper divisors (1).

19957969 is an equidigital number, since it uses as much as digits as its factorization.

19957969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1377810, while the sum is 55.

The square root of 19957969 is about 4467.4342748383. The cubic root of 19957969 is about 271.2514788228.

The spelling of 19957969 in words is "nineteen million, nine hundred fifty-seven thousand, nine hundred sixty-nine".