129458278257656 has 16 divisors (see below), whose sum is σ = 242743824444840. Its totient is φ = 64726591739040.

The previous prime is 129458278257647. The next prime is 129458278257667. The reversal of 129458278257656 is 656752872854921.

It is a super-2 number, since 2×129458278257656² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318207731 + ... + 318614306.

Almost surely, 2^{129458278257656} is an apocalyptic number.

It is an amenable number.

129458278257656 is a deficient number, since it is larger than the sum of its proper divisors (113285546187184).

129458278257656 is a wasteful number, since it uses less digits than its factorization.

129458278257656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636847454 (or 636847450 counting only the distinct ones).

The product of its digits is 4064256000, while the sum is 77.

The spelling of 129458278257656 in words is "one hundred twenty-nine trillion, four hundred fifty-eight billion, two hundred seventy-eight million, two hundred fifty-seven thousand, six hundred fifty-six".