139591685 has 4 divisors (see below), whose sum is σ = 167510028. Its totient is φ = 111673344.

The previous prime is 139591663. The next prime is 139591687. The reversal of 139591685 is 586195931.

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 60435076 + 79156609 = 7774^2 + 8897^2 .

It is a cyclic number.

It is not a de Polignac number, because 139591685 - 2¹⁴ = 139575301 is a prime.

It is a super-2 number, since 2×139591685² = 38971677042278450, 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 (139591687) 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, 13959164 + ... + 13959173.

It is an arithmetic number, because the mean of its divisors is an integer number (41877507).

Almost surely, 2^139591685 is an apocalyptic number.

It is an amenable number.

139591685 is a deficient number, since it is larger than the sum of its proper divisors (27918343).

139591685 is an equidigital number, since it uses as much as digits as its factorization.

139591685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27918342.

The product of its digits is 291600, while the sum is 47.

The square root of 139591685 is about 11814.8925090328. The cubic root of 139591685 is about 518.7441154798.

The spelling of 139591685 in words is "one hundred thirty-nine million, five hundred ninety-one thousand, six hundred eighty-five".