129978887 has 8 divisors (see below), whose sum is σ = 131783376. Its totient is φ = 128187072.

The previous prime is 129978883. The next prime is 129978941. The reversal of 129978887 is 788879921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 129978887 - 2² = 129978883 is a prime.

It is a super-2 number, since 2×129978887² = 33789022131517538, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129978883) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18488 + ... + 24530.

It is an arithmetic number, because the mean of its divisors is an integer number (16472922).

Almost surely, 2^129978887 is an apocalyptic number.

129978887 is a deficient number, since it is larger than the sum of its proper divisors (1804489).

129978887 is a wasteful number, since it uses less digits than its factorization.

129978887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6337.

The product of its digits is 4064256, while the sum is 59.

The square root of 129978887 is about 11400.8283470983. The cubic root of 129978887 is about 506.5522762785.

The spelling of 129978887 in words is "one hundred twenty-nine million, nine hundred seventy-eight thousand, eight hundred eighty-seven".