19431962261 has 2 divisors, whose sum is σ = 19431962262. Its totient is φ = 19431962260.

The previous prime is 19431962243. The next prime is 19431962267. The reversal of 19431962261 is 16226913491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17133239236 + 2298723025 = 130894^2 + 47945^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19431962261 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19431962267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9715981130 + 9715981131.

It is an arithmetic number, because the mean of its divisors is an integer number (9715981131).

Almost surely, 2^19431962261 is an apocalyptic number.

It is an amenable number.

19431962261 is a deficient number, since it is larger than the sum of its proper divisors (1).

19431962261 is an equidigital number, since it uses as much as digits as its factorization.

19431962261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 44.

The spelling of 19431962261 in words is "nineteen billion, four hundred thirty-one million, nine hundred sixty-two thousand, two hundred sixty-one".