129970991 has 4 divisors (see below), whose sum is σ = 130414872. Its totient is φ = 129527112.

The previous prime is 129970957. The next prime is 129970993. The reversal of 129970991 is 199079921.

It is a happy number.

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-129970991 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 (129970993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 221501 + ... + 222086.

It is an arithmetic number, because the mean of its divisors is an integer number (32603718).

Almost surely, 2^129970991 is an apocalyptic number.

129970991 is a deficient number, since it is larger than the sum of its proper divisors (443881).

129970991 is an equidigital number, since it uses as much as digits as its factorization.

129970991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443880.

The product of its (nonzero) digits is 91854, while the sum is 47.

The square root of 129970991 is about 11400.4820512117. The cubic root of 129970991 is about 506.5420186696.

The spelling of 129970991 in words is "one hundred twenty-nine million, nine hundred seventy thousand, nine hundred ninety-one".