129939889 has 4 divisors (see below), whose sum is σ = 132142320. Its totient is φ = 127737460.

The previous prime is 129939877. The next prime is 129939907. The reversal of 129939889 is 988939921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 988939921 = 151 ⋅6549271.

It is a cyclic number.

It is not a de Polignac number, because 129939889 - 2¹⁵ = 129907121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129939809) 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, 1101127 + ... + 1101244.

It is an arithmetic number, because the mean of its divisors is an integer number (33035580).

Almost surely, 2^129939889 is an apocalyptic number.

It is an amenable number.

129939889 is a deficient number, since it is larger than the sum of its proper divisors (2202431).

129939889 is an equidigital number, since it uses as much as digits as its factorization.

129939889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2202430.

The product of its digits is 2519424, while the sum is 58.

The square root of 129939889 is about 11399.1179044696. The cubic root of 129939889 is about 506.5016103534.

The spelling of 129939889 in words is "one hundred twenty-nine million, nine hundred thirty-nine thousand, eight hundred eighty-nine".