252979981 has 2 divisors, whose sum is σ = 252979982. Its totient is φ = 252979980.

The previous prime is 252979957. The next prime is 252979999. The reversal of 252979981 is 189979252.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244766025 + 8213956 = 15645^2 + 2866^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-252979981 is a prime.

It is a super-2 number, since 2×252979981² = 127997741573520722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (252979901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126489990 + 126489991.

It is an arithmetic number, because the mean of its divisors is an integer number (126489991).

Almost surely, 2^252979981 is an apocalyptic number.

It is an amenable number.

252979981 is a deficient number, since it is larger than the sum of its proper divisors (1).

252979981 is an equidigital number, since it uses as much as digits as its factorization.

252979981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 816480, while the sum is 52.

The square root of 252979981 is about 15905.3444162646. The cubic root of 252979981 is about 632.4536721836.

The spelling of 252979981 in words is "two hundred fifty-two million, nine hundred seventy-nine thousand, nine hundred eighty-one".