193904639 has 2 divisors, whose sum is σ = 193904640. Its totient is φ = 193904638.

The previous prime is 193904617. The next prime is 193904653. The reversal of 193904639 is 936409391.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-193904639 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 193904639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (193904699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 96952319 + 96952320.

It is an arithmetic number, because the mean of its divisors is an integer number (96952320).

Almost surely, 2^193904639 is an apocalyptic number.

193904639 is a deficient number, since it is larger than the sum of its proper divisors (1).

193904639 is an equidigital number, since it uses as much as digits as its factorization.

193904639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 157464, while the sum is 44.

The square root of 193904639 is about 13924.9645960053. The cubic root of 193904639 is about 578.8011692463.

The spelling of 193904639 in words is "one hundred ninety-three million, nine hundred four thousand, six hundred thirty-nine".