139664361 has 4 divisors (see below), whose sum is σ = 186219152. Its totient is φ = 93109572.

The previous prime is 139664353. The next prime is 139664363. The reversal of 139664361 is 163466931.

139664361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 163466931 = 3 ⋅54488977.

It is not a de Polignac number, because 139664361 - 2³ = 139664353 is a prime.

It is a super-2 number, since 2×139664361² = 39012267467076642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139664363) 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, 23277391 + ... + 23277396.

It is an arithmetic number, because the mean of its divisors is an integer number (46554788).

Almost surely, 2^139664361 is an apocalyptic number.

It is an amenable number.

139664361 is a deficient number, since it is larger than the sum of its proper divisors (46554791).

139664361 is an equidigital number, since it uses as much as digits as its factorization.

139664361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46554790.

The product of its digits is 69984, while the sum is 39.

The square root of 139664361 is about 11817.9677186900. The cubic root of 139664361 is about 518.8341249159.

The spelling of 139664361 in words is "one hundred thirty-nine million, six hundred sixty-four thousand, three hundred sixty-one".