168421751731 has 2 divisors, whose sum is σ = 168421751732. Its totient is φ = 168421751730.

The previous prime is 168421751683. The next prime is 168421751747. The reversal of 168421751731 is 137157124861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 168421751731 - 2²⁷ = 168287534003 is a prime.

It is a super-2 number, since 2×168421751731² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (168421751791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84210875865 + 84210875866.

It is an arithmetic number, because the mean of its divisors is an integer number (84210875866).

Almost surely, 2^168421751731 is an apocalyptic number.

168421751731 is a deficient number, since it is larger than the sum of its proper divisors (1).

168421751731 is an equidigital number, since it uses as much as digits as its factorization.

168421751731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 282240, while the sum is 46.

The spelling of 168421751731 in words is "one hundred sixty-eight billion, four hundred twenty-one million, seven hundred fifty-one thousand, seven hundred thirty-one".