139907986 has 4 divisors (see below), whose sum is σ = 209861982. Its totient is φ = 69953992.

The previous prime is 139907923. The next prime is 139908017. The reversal of 139907986 is 689709931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 689709931 = 8831 ⋅78101.

It can be written as a sum of positive squares in only one way, i.e., 114597025 + 25310961 = 10705^2 + 5031^2 .

It is a super-3 number, since 3×139907986³ (a number of 25 digits) contains 333 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34976995 + ... + 34976998.

Almost surely, 2^139907986 is an apocalyptic number.

139907986 is a deficient number, since it is larger than the sum of its proper divisors (69953996).

139907986 is an equidigital number, since it uses as much as digits as its factorization.

139907986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69953995.

The product of its (nonzero) digits is 734832, while the sum is 52.

The square root of 139907986 is about 11828.2706259199. The cubic root of 139907986 is about 519.1356275986.

The spelling of 139907986 in words is "one hundred thirty-nine million, nine hundred seven thousand, nine hundred eighty-six".