168426379981 has 2 divisors, whose sum is σ = 168426379982. Its totient is φ = 168426379980.

The previous prime is 168426379949. The next prime is 168426380029. The reversal of 168426379981 is 189973624861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 153860062500 + 14566317481 = 392250^2 + 120691^2 .

It is an emirp because it is prime and its reverse (189973624861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 168426379981 - 2⁵ = 168426379949 is a prime.

It is a super-3 number, since 3×168426379981³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (168426374981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84213189990 + 84213189991.

It is an arithmetic number, because the mean of its divisors is an integer number (84213189991).

Almost surely, 2^168426379981 is an apocalyptic number.

It is an amenable number.

168426379981 is a deficient number, since it is larger than the sum of its proper divisors (1).

168426379981 is an equidigital number, since it uses as much as digits as its factorization.

168426379981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31352832, while the sum is 64.

The spelling of 168426379981 in words is "one hundred sixty-eight billion, four hundred twenty-six million, three hundred seventy-nine thousand, nine hundred eighty-one".