139756906 has 4 divisors (see below), whose sum is σ = 209635362. Its totient is φ = 69878452.

The previous prime is 139756891. The next prime is 139756907. The reversal of 139756906 is 609657931.

139756906 is digitally balanced in base 3, 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 an emirpimes, since its reverse is a distinct semiprime: 609657931 = 79 ⋅7717189.

It can be written as a sum of positive squares in only one way, i.e., 134351281 + 5405625 = 11591^2 + 2325^2 .

It is not an unprimeable number, because it can be changed into a prime (139756907) 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 as a sum of consecutive naturals, namely, 34939225 + ... + 34939228.

Almost surely, 2^139756906 is an apocalyptic number.

139756906 is a deficient number, since it is larger than the sum of its proper divisors (69878456).

139756906 is an equidigital number, since it uses as much as digits as its factorization.

139756906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69878455.

The product of its (nonzero) digits is 306180, while the sum is 46.

The square root of 139756906 is about 11821.8825066061. The cubic root of 139756906 is about 518.9486969805.

The spelling of 139756906 in words is "one hundred thirty-nine million, seven hundred fifty-six thousand, nine hundred six".