19943256407 has 2 divisors, whose sum is σ = 19943256408. Its totient is φ = 19943256406.

The previous prime is 19943256379. The next prime is 19943256419. The reversal of 19943256407 is 70465234991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19943256407 - 2²⁸ = 19674820951 is a prime.

It is a super-2 number, since 2×19943256407² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19943256497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9971628203 + 9971628204.

It is an arithmetic number, because the mean of its divisors is an integer number (9971628204).

Almost surely, 2^19943256407 is an apocalyptic number.

19943256407 is a deficient number, since it is larger than the sum of its proper divisors (1).

19943256407 is an equidigital number, since it uses as much as digits as its factorization.

19943256407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The spelling of 19943256407 in words is "nineteen billion, nine hundred forty-three million, two hundred fifty-six thousand, four hundred seven".