139377979 has 4 divisors (see below), whose sum is σ = 150099376. Its totient is φ = 128656584.

The previous prime is 139377971. The next prime is 139377991. The reversal of 139377979 is 979773931.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 979773931 = 19 ⋅51567049.

It is a cyclic number.

It is not a de Polignac number, because 139377979 - 2³ = 139377971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139377971) 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, 5360679 + ... + 5360704.

It is an arithmetic number, because the mean of its divisors is an integer number (37524844).

Almost surely, 2^139377979 is an apocalyptic number.

139377979 is a deficient number, since it is larger than the sum of its proper divisors (10721397).

139377979 is a wasteful number, since it uses less digits than its factorization.

139377979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10721396.

The product of its digits is 2250423, while the sum is 55.

The square root of 139377979 is about 11805.8451201089. The cubic root of 139377979 is about 518.4792588477.

The spelling of 139377979 in words is "one hundred thirty-nine million, three hundred seventy-seven thousand, nine hundred seventy-nine".