68199581 has 2 divisors, whose sum is σ = 68199582. Its totient is φ = 68199580.

The previous prime is 68199511. The next prime is 68199587. The reversal of 68199581 is 18599186.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34164025 + 34035556 = 5845^2 + 5834^2 .

It is a cyclic number.

It is not a de Polignac number, because 68199581 - 2¹⁴ = 68183197 is a prime.

It is a super-2 number, since 2×68199581² = 9302365697151122, 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 (68199587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34099790 + 34099791.

It is an arithmetic number, because the mean of its divisors is an integer number (34099791).

Almost surely, 2^68199581 is an apocalyptic number.

It is an amenable number.

68199581 is a deficient number, since it is larger than the sum of its proper divisors (1).

68199581 is an equidigital number, since it uses as much as digits as its factorization.

68199581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 47.

The square root of 68199581 is about 8258.3037604583. The cubic root of 68199581 is about 408.5644440786.

The spelling of 68199581 in words is "sixty-eight million, one hundred ninety-nine thousand, five hundred eighty-one".