68156573477 has 4 divisors (see below), whose sum is σ = 68158910976. Its totient is φ = 68154235980.

The previous prime is 68156573473. The next prime is 68156573483. The reversal of 68156573477 is 77437565186.

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: 77437565186 = 2 ⋅38718782593.

It is a cyclic number.

It is not a de Polignac number, because 68156573477 - 2² = 68156573473 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68156573473) 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, 1124453 + ... + 1183514.

It is an arithmetic number, because the mean of its divisors is an integer number (17039727744).

Almost surely, 2^68156573477 is an apocalyptic number.

It is an amenable number.

68156573477 is a deficient number, since it is larger than the sum of its proper divisors (2337499).

68156573477 is a wasteful number, since it uses less digits than its factorization.

68156573477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2337498.

The product of its digits is 29635200, while the sum is 59.

The spelling of 68156573477 in words is "sixty-eight billion, one hundred fifty-six million, five hundred seventy-three thousand, four hundred seventy-seven".