68045981 has 2 divisors, whose sum is σ = 68045982. Its totient is φ = 68045980.

The previous prime is 68045963. The next prime is 68046007. The reversal of 68045981 is 18954086.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39262756 + 28783225 = 6266^2 + 5365^2 .

It is a cyclic number.

It is not a de Polignac number, because 68045981 - 2¹⁰ = 68044957 is a prime.

It is a super-2 number, since 2×68045981² = 9260511060504722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68045911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34022990 + 34022991.

It is an arithmetic number, because the mean of its divisors is an integer number (34022991).

Almost surely, 2^68045981 is an apocalyptic number.

It is an amenable number.

68045981 is a deficient number, since it is larger than the sum of its proper divisors (1).

68045981 is an equidigital number, since it uses as much as digits as its factorization.

68045981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 68045981 is about 8248.9987877318. The cubic root of 68045981 is about 408.2574887687.

The spelling of 68045981 in words is "sixty-eight million, forty-five thousand, nine hundred eighty-one".