68877947657 has 4 divisors (see below), whose sum is σ = 69238565376. Its totient is φ = 68517329940.

The previous prime is 68877947639. The next prime is 68877947729. The reversal of 68877947657 is 75674977886.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75674977886 = 2 ⋅37837488943.

It is a cyclic number.

It is not a de Polignac number, because 68877947657 - 2¹⁰ = 68877946633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68877947627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180308573 + ... + 180308954.

It is an arithmetic number, because the mean of its divisors is an integer number (17309641344).

Almost surely, 2^68877947657 is an apocalyptic number.

It is an amenable number.

68877947657 is a deficient number, since it is larger than the sum of its proper divisors (360617719).

68877947657 is a wasteful number, since it uses less digits than its factorization.

68877947657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360617718.

The product of its digits is 995742720, while the sum is 74.

The spelling of 68877947657 in words is "sixty-eight billion, eight hundred seventy-seven million, nine hundred forty-seven thousand, six hundred fifty-seven".