129157891 has 8 divisors (see below), whose sum is σ = 138111264. Its totient is φ = 120355200.

The previous prime is 129157883. The next prime is 129157921. The reversal of 129157891 is 198751921.

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 129157891 - 2³ = 129157883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129157291) 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, 35895 + ... + 39328.

It is an arithmetic number, because the mean of its divisors is an integer number (17263908).

Almost surely, 2^129157891 is an apocalyptic number.

129157891 is a deficient number, since it is larger than the sum of its proper divisors (8953373).

129157891 is a wasteful number, since it uses less digits than its factorization.

129157891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75341.

The product of its digits is 45360, while the sum is 43.

The square root of 129157891 is about 11364.7653297373. The cubic root of 129157891 is about 505.4834973381.

The spelling of 129157891 in words is "one hundred twenty-nine million, one hundred fifty-seven thousand, eight hundred ninety-one".