139645031 has 4 divisors (see below), whose sum is σ = 141000912. Its totient is φ = 138289152.

The previous prime is 139645027. The next prime is 139645039. The reversal of 139645031 is 130546931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 130546931 = 11117 ⋅11743.

It is a cyclic number.

It is not a de Polignac number, because 139645031 - 2² = 139645027 is a prime.

It is a super-2 number, since 2×139645031² = 39001469365981922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139645039) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 677786 + ... + 677991.

It is an arithmetic number, because the mean of its divisors is an integer number (35250228).

Almost surely, 2^139645031 is an apocalyptic number.

139645031 is a deficient number, since it is larger than the sum of its proper divisors (1355881).

139645031 is a wasteful number, since it uses less digits than its factorization.

139645031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1355880.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 139645031 is about 11817.1498678827. The cubic root of 139645031 is about 518.8101877037.

The spelling of 139645031 in words is "one hundred thirty-nine million, six hundred forty-five thousand, thirty-one".