129155101 has 4 divisors (see below), whose sum is σ = 132158752. Its totient is φ = 126151452.

The previous prime is 129155023. The next prime is 129155111. The reversal of 129155101 is 101551921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 129155101 - 2¹⁷ = 129024029 is a prime.

It is a super-2 number, since 2×129155101² = 33362080228640402, 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 (129155111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1501761 + ... + 1501846.

It is an arithmetic number, because the mean of its divisors is an integer number (33039688).

Almost surely, 2^129155101 is an apocalyptic number.

It is an amenable number.

129155101 is a deficient number, since it is larger than the sum of its proper divisors (3003651).

129155101 is an equidigital number, since it uses as much as digits as its factorization.

129155101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3003650.

The product of its (nonzero) digits is 450, while the sum is 25.

The square root of 129155101 is about 11364.6425812693. The cubic root of 129155101 is about 505.4798575834.

The spelling of 129155101 in words is "one hundred twenty-nine million, one hundred fifty-five thousand, one hundred one".