139371665 has 4 divisors (see below), whose sum is σ = 167246004. Its totient is φ = 111497328.

The previous prime is 139371653. The next prime is 139371667. The reversal of 139371665 is 566173931.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 47997184 + 91374481 = 6928^2 + 9559^2 .

It is a cyclic number.

It is not a de Polignac number, because 139371665 - 2⁸ = 139371409 is a prime.

It is a super-2 number, since 2×139371665² = 38848922009744450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139371667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13937162 + ... + 13937171.

It is an arithmetic number, because the mean of its divisors is an integer number (41811501).

Almost surely, 2^139371665 is an apocalyptic number.

It is an amenable number.

139371665 is a deficient number, since it is larger than the sum of its proper divisors (27874339).

139371665 is an equidigital number, since it uses as much as digits as its factorization.

139371665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27874338.

The product of its digits is 102060, while the sum is 41.

The square root of 139371665 is about 11805.5777071688. The cubic root of 139371665 is about 518.4714294725.

The spelling of 139371665 in words is "one hundred thirty-nine million, three hundred seventy-one thousand, six hundred sixty-five".