129666625 has 24 divisors (see below), whose sum is σ = 177893352. Its totient is φ = 94292000.

The previous prime is 129666577. The next prime is 129666637. The reversal of 129666625 is 526666921.

It can be written as a sum of positive squares in 4 ways, for example, as 11553201 + 118113424 = 3399^2 + 10868^2 .

It is not a de Polignac number, because 129666625 - 2¹³ = 129658433 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10839 + ... + 19411.

It is an arithmetic number, because the mean of its divisors is an integer number (7412223).

Almost surely, 2^129666625 is an apocalyptic number.

It is an amenable number.

129666625 is a deficient number, since it is larger than the sum of its proper divisors (48226727).

129666625 is an equidigital number, since it uses as much as digits as its factorization.

129666625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8610 (or 8589 counting only the distinct ones).

The product of its digits is 233280, while the sum is 43.

The square root of 129666625 is about 11387.1254054744. The cubic root of 129666625 is about 506.1463030000.

It can be divided in two parts, 12966 and 6625, that added together give a palindrome (19591).

The spelling of 129666625 in words is "one hundred twenty-nine million, six hundred sixty-six thousand, six hundred twenty-five".