129957919 has 8 divisors (see below), whose sum is σ = 159948320. Its totient is φ = 102823776.

The previous prime is 129957917. The next prime is 129957931. The reversal of 129957919 is 919759921.

It is a happy number.

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 129957919 - 2¹ = 129957917 is a prime.

It is a super-2 number, since 2×129957919² = 33778121421621122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129957917) 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, 713964 + ... + 714145.

It is an arithmetic number, because the mean of its divisors is an integer number (19993540).

Almost surely, 2^129957919 is an apocalyptic number.

129957919 is a deficient number, since it is larger than the sum of its proper divisors (29990401).

129957919 is a wasteful number, since it uses less digits than its factorization.

129957919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1428129.

The product of its digits is 459270, while the sum is 52.

The square root of 129957919 is about 11399.9087277048. The cubic root of 129957919 is about 506.5250360614.

The spelling of 129957919 in words is "one hundred twenty-nine million, nine hundred fifty-seven thousand, nine hundred nineteen".