129825517 has 4 divisors (see below), whose sum is σ = 130368960. Its totient is φ = 129282076.

The previous prime is 129825511. The next prime is 129825523. The reversal of 129825517 is 715528921.

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, and also an emirpimes, since its reverse is a distinct semiprime: 715528921 = 347 ⋅2062043.

It is an interprime number because it is at equal distance from previous prime (129825511) and next prime (129825523).

It is a cyclic number.

It is not a de Polignac number, because 129825517 - 2¹⁹ = 129301229 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129825517.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129825511) 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, 271363 + ... + 271840.

It is an arithmetic number, because the mean of its divisors is an integer number (32592240).

Almost surely, 2^129825517 is an apocalyptic number.

It is an amenable number.

129825517 is a deficient number, since it is larger than the sum of its proper divisors (543443).

129825517 is an equidigital number, since it uses as much as digits as its factorization.

129825517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543442.

The product of its digits is 50400, while the sum is 40.

The square root of 129825517 is about 11394.1000961024. The cubic root of 129825517 is about 506.3529605756.

The spelling of 129825517 in words is "one hundred twenty-nine million, eight hundred twenty-five thousand, five hundred seventeen".