268163751681 has 40 divisors (see below), whose sum is σ = 459446997504. Its totient is φ = 152691013440.

The previous prime is 268163751643. The next prime is 268163751703. The reversal of 268163751681 is 186157361862.

It is a happy number.

268163751681 is a `hidden beast` number, since 2 + 6 + 8 + 16 + 37 + 516 + 81 = 666.

It is not a de Polignac number, because 268163751681 - 2⁷ = 268163751553 is a prime.

It is a super-2 number, since 2×268163751681² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (268163751601) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 682225 + ... + 1000878.

Almost surely, 2^268163751681 is an apocalyptic number.

268163751681 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

268163751681 is a deficient number, since it is larger than the sum of its proper divisors (191283245823).

268163751681 is a wasteful number, since it uses less digits than its factorization.

268163751681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1683403 (or 1683394 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 54.

The spelling of 268163751681 in words is "two hundred sixty-eight billion, one hundred sixty-three million, seven hundred fifty-one thousand, six hundred eighty-one".