129902569 has 4 divisors (see below), whose sum is σ = 130050900. Its totient is φ = 129754240.

The previous prime is 129902567. The next prime is 129902579. The reversal of 129902569 is 965209921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 965209921 = 13 ⋅74246917.

It can be written as a sum of positive squares in 2 ways, for example, as 6692569 + 123210000 = 2587^2 + 11100^2 .

It is a cyclic number.

It is not a de Polignac number, because 129902569 - 2¹ = 129902567 is a prime.

It is a super-2 number, since 2×129902569² = 33749354865599522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129902561) 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, 72844 + ... + 74605.

It is an arithmetic number, because the mean of its divisors is an integer number (32512725).

Almost surely, 2^129902569 is an apocalyptic number.

It is an amenable number.

129902569 is a deficient number, since it is larger than the sum of its proper divisors (148331).

129902569 is an equidigital number, since it uses as much as digits as its factorization.

129902569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148330.

The product of its (nonzero) digits is 87480, while the sum is 43.

The square root of 129902569 is about 11397.4808181457. The cubic root of 129902569 is about 506.4531149806.

The spelling of 129902569 in words is "one hundred twenty-nine million, nine hundred two thousand, five hundred sixty-nine".