139806977 has 4 divisors (see below), whose sum is σ = 139921236. Its totient is φ = 139692720.

The previous prime is 139806971. The next prime is 139807021. The reversal of 139806977 is 779608931.

It is a Cunningham number, because it is equal to 11824²+1.

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 105596176 + 34210801 = 10276^2 + 5849^2 .

It is a cyclic number.

It is not a de Polignac number, because 139806977 - 2⁶ = 139806913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139806971) 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, 55274 + ... + 57747.

It is an arithmetic number, because the mean of its divisors is an integer number (34980309).

Almost surely, 2^139806977 is an apocalyptic number.

It is an amenable number.

139806977 is a deficient number, since it is larger than the sum of its proper divisors (114259).

139806977 is a wasteful number, since it uses less digits than its factorization.

139806977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114258.

The product of its (nonzero) digits is 571536, while the sum is 50.

The square root of 139806977 is about 11824.0000422869. Note that the first 4 decimals coincide. The cubic root of 139806977 is about 519.0106645269.

The spelling of 139806977 in words is "one hundred thirty-nine million, eight hundred six thousand, nine hundred seventy-seven".