129721325 has 12 divisors (see below), whose sum is σ = 164596608. Its totient is φ = 101362800.

The previous prime is 129721307. The next prime is 129721351. The reversal of 129721325 is 523127921.

It is not a de Polignac number, because 129721325 - 2⁸ = 129721069 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 129721291 and 129721300.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 59261 + ... + 61410.

It is an arithmetic number, because the mean of its divisors is an integer number (13716384).

Almost surely, 2^129721325 is an apocalyptic number.

It is an amenable number.

129721325 is a deficient number, since it is larger than the sum of its proper divisors (34875283).

129721325 is a wasteful number, since it uses less digits than its factorization.

129721325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120724 (or 120719 counting only the distinct ones).

The product of its digits is 7560, while the sum is 32.

The square root of 129721325 is about 11389.5269875443. The cubic root of 129721325 is about 506.2174657749.

It can be divided in two parts, 1297 and 21325, that added together give a palindrome (22622).

The spelling of 129721325 in words is "one hundred twenty-nine million, seven hundred twenty-one thousand, three hundred twenty-five".