1399139391 has 32 divisors (see below), whose sum is σ = 2067549120. Its totient is φ = 836121600.

The previous prime is 1399139377. The next prime is 1399139431. The reversal of 1399139391 is 1939319931.

It is not a de Polignac number, because 1399139391 - 2⁶ = 1399139327 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1399139391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1399139311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 364261 + ... + 368081.

It is an arithmetic number, because the mean of its divisors is an integer number (64610910).

Almost surely, 2^1399139391 is an apocalyptic number.

1399139391 is a deficient number, since it is larger than the sum of its proper divisors (668409729).

1399139391 is a wasteful number, since it uses less digits than its factorization.

1399139391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4107.

The product of its digits is 177147, while the sum is 48.

The square root of 1399139391 is about 37405.0717283098. The cubic root of 1399139391 is about 1118.4596680066.

The spelling of 1399139391 in words is "one billion, three hundred ninety-nine million, one hundred thirty-nine thousand, three hundred ninety-one".