129657 has 8 divisors (see below), whose sum is σ = 188640. Its totient is φ = 78560.

The previous prime is 129643. The next prime is 129671. The reversal of 129657 is 756921.

It is an interprime number because it is at equal distance from previous prime (129643) and next prime (129671).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 129657 - 2⁴ = 129641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129607) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1932 + ... + 1997.

It is an arithmetic number, because the mean of its divisors is an integer number (23580).

2¹²⁹⁶⁵⁷ is an apocalyptic number.

It is an amenable number.

129657 is a deficient number, since it is larger than the sum of its proper divisors (58983).

129657 is a wasteful number, since it uses less digits than its factorization.

129657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3943.

The product of its digits is 3780, while the sum is 30.

The square root of 129657 is about 360.0791579639. The cubic root of 129657 is about 50.6133779143.

Subtracting 129657 from its reverse (756921), we obtain a square (627264 = 792²).

It can be divided in two parts, 12 and 9657, that added together give a palindrome (9669).

The spelling of 129657 in words is "one hundred twenty-nine thousand, six hundred fifty-seven".