252605981 has 2 divisors, whose sum is σ = 252605982. Its totient is φ = 252605980.

The previous prime is 252605971. The next prime is 252605999. The reversal of 252605981 is 189506252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 230128900 + 22477081 = 15170^2 + 4741^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-252605981 is a prime.

It is a super-2 number, since 2×252605981² = 127619563273944722, 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 (252605971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126302990 + 126302991.

It is an arithmetic number, because the mean of its divisors is an integer number (126302991).

Almost surely, 2^252605981 is an apocalyptic number.

It is an amenable number.

252605981 is a deficient number, since it is larger than the sum of its proper divisors (1).

252605981 is an equidigital number, since it uses as much as digits as its factorization.

252605981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43200, while the sum is 38.

The square root of 252605981 is about 15893.5830132793. The cubic root of 252605981 is about 632.1418499697.

The spelling of 252605981 in words is "two hundred fifty-two million, six hundred five thousand, nine hundred eighty-one".