138762391 has 2 divisors, whose sum is σ = 138762392. Its totient is φ = 138762390.

The previous prime is 138762367. The next prime is 138762401. The reversal of 138762391 is 193267831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138762391 - 2⁹ = 138761879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138762311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69381195 + 69381196.

It is an arithmetic number, because the mean of its divisors is an integer number (69381196).

Almost surely, 2^138762391 is an apocalyptic number.

138762391 is a deficient number, since it is larger than the sum of its proper divisors (1).

138762391 is an equidigital number, since it uses as much as digits as its factorization.

138762391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 40.

The square root of 138762391 is about 11779.7449463051. The cubic root of 138762391 is about 517.7148132284.

The spelling of 138762391 in words is "one hundred thirty-eight million, seven hundred sixty-two thousand, three hundred ninety-one".