19993404667 has 2 divisors, whose sum is σ = 19993404668. Its totient is φ = 19993404666.

The previous prime is 19993404617. The next prime is 19993404689. The reversal of 19993404667 is 76640439991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 19993404667 - 2²³ = 19985016059 is a prime.

It is not a weakly prime, because it can be changed into another prime (19993404617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9996702333 + 9996702334.

It is an arithmetic number, because the mean of its divisors is an integer number (9996702334).

Almost surely, 2^19993404667 is an apocalyptic number.

19993404667 is a deficient number, since it is larger than the sum of its proper divisors (1).

19993404667 is an equidigital number, since it uses as much as digits as its factorization.

19993404667 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8817984, while the sum is 58.

The spelling of 19993404667 in words is "nineteen billion, nine hundred ninety-three million, four hundred four thousand, six hundred sixty-seven".