268561621 has 2 divisors, whose sum is σ = 268561622. Its totient is φ = 268561620.

The previous prime is 268561613. The next prime is 268561681. The reversal of 268561621 is 126165862.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171243396 + 97318225 = 13086^2 + 9865^2 .

It is a cyclic number.

It is not a de Polignac number, because 268561621 - 2³ = 268561613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (268561681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 134280810 + 134280811.

It is an arithmetic number, because the mean of its divisors is an integer number (134280811).

Almost surely, 2^268561621 is an apocalyptic number.

It is an amenable number.

268561621 is a deficient number, since it is larger than the sum of its proper divisors (1).

268561621 is an equidigital number, since it uses as much as digits as its factorization.

268561621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 37.

The square root of 268561621 is about 16387.8497979448. The cubic root of 268561621 is about 645.1806244531.

The spelling of 268561621 in words is "two hundred sixty-eight million, five hundred sixty-one thousand, six hundred twenty-one".