139659987 has 6 divisors (see below), whose sum is σ = 186240612. Its totient is φ = 93093012.

The previous prime is 139659973. The next prime is 139659997. The reversal of 139659987 is 789956931.

It is not a de Polignac number, because 139659987 - 2⁷ = 139659859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139659907) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17058 + ... + 23880.

It is an arithmetic number, because the mean of its divisors is an integer number (31040102).

Almost surely, 2^139659987 is an apocalyptic number.

139659987 is a deficient number, since it is larger than the sum of its proper divisors (46580625).

139659987 is an frugal number, since it uses more digits than its factorization.

139659987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13649 (or 6826 counting only the distinct ones).

The product of its digits is 3674160, while the sum is 57.

The square root of 139659987 is about 11817.7826600424. The cubic root of 139659987 is about 518.8287085875.

The spelling of 139659987 in words is "one hundred thirty-nine million, six hundred fifty-nine thousand, nine hundred eighty-seven".