129256645 has 16 divisors (see below), whose sum is σ = 177510528. Its totient is φ = 88511040.

The previous prime is 129256643. The next prime is 129256681. The reversal of 129256645 is 546652921.

It is not a de Polignac number, because 129256645 - 2¹ = 129256643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 129256598 and 129256607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129256643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28590 + ... + 32800.

It is an arithmetic number, because the mean of its divisors is an integer number (11094408).

Almost surely, 2^129256645 is an apocalyptic number.

It is an amenable number.

129256645 is a deficient number, since it is larger than the sum of its proper divisors (48253883).

129256645 is an equidigital number, since it uses as much as digits as its factorization.

129256645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5100.

The product of its digits is 129600, while the sum is 40.

The square root of 129256645 is about 11369.1092439118. The cubic root of 129256645 is about 505.6122952503.

The spelling of 129256645 in words is "one hundred twenty-nine million, two hundred fifty-six thousand, six hundred forty-five".