139666522 has 4 divisors (see below), whose sum is σ = 209499786. Its totient is φ = 69833260.

The previous prime is 139666487. The next prime is 139666589. The reversal of 139666522 is 225666931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 225666931 = 7 ⋅32238133.

It can be written as a sum of positive squares in only one way, i.e., 108764041 + 30902481 = 10429^2 + 5559^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 34916629 + ... + 34916632.

Almost surely, 2^139666522 is an apocalyptic number.

139666522 is a deficient number, since it is larger than the sum of its proper divisors (69833264).

139666522 is an equidigital number, since it uses as much as digits as its factorization.

139666522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69833263.

The product of its digits is 116640, while the sum is 40.

The square root of 139666522 is about 11818.0591469158. The cubic root of 139666522 is about 518.8368008426.

The spelling of 139666522 in words is "one hundred thirty-nine million, six hundred sixty-six thousand, five hundred twenty-two".