129940087 has 4 divisors (see below), whose sum is σ = 135589680. Its totient is φ = 124290496.

The previous prime is 129940043. The next prime is 129940091. The reversal of 129940087 is 780049921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129940087 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129940787) 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, 2824762 + ... + 2824807.

It is an arithmetic number, because the mean of its divisors is an integer number (33897420).

Almost surely, 2^129940087 is an apocalyptic number.

129940087 is a deficient number, since it is larger than the sum of its proper divisors (5649593).

129940087 is an equidigital number, since it uses as much as digits as its factorization.

129940087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5649592.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 129940087 is about 11399.1265893489. The cubic root of 129940087 is about 506.5018676192.

The spelling of 129940087 in words is "one hundred twenty-nine million, nine hundred forty thousand, eighty-seven".