139823991 has 6 divisors (see below), whose sum is σ = 201968000. Its totient is φ = 93215988.

The previous prime is 139823977. The next prime is 139824011. The reversal of 139823991 is 199328931.

It is a happy number.

It is not a de Polignac number, because 139823991 - 2⁷ = 139823863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139823291) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7767991 + ... + 7768008.

Almost surely, 2^139823991 is an apocalyptic number.

139823991 is a deficient number, since it is larger than the sum of its proper divisors (62144009).

139823991 is a wasteful number, since it uses less digits than its factorization.

139823991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15536005 (or 15536002 counting only the distinct ones).

The product of its digits is 104976, while the sum is 45.

The square root of 139823991 is about 11824.7194892733. The cubic root of 139823991 is about 519.0317175756.

The spelling of 139823991 in words is "one hundred thirty-nine million, eight hundred twenty-three thousand, nine hundred ninety-one".