253965661 has 4 divisors (see below), whose sum is σ = 254832732. Its totient is φ = 253098592.

The previous prime is 253965659. The next prime is 253965707. The reversal of 253965661 is 166569352.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 250240761 + 3724900 = 15819^2 + 1930^2 .

It is a cyclic number.

It is not a de Polignac number, because 253965661 - 2¹ = 253965659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253915661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 433096 + ... + 433681.

It is an arithmetic number, because the mean of its divisors is an integer number (63708183).

Almost surely, 2^253965661 is an apocalyptic number.

It is an amenable number.

253965661 is a deficient number, since it is larger than the sum of its proper divisors (867071).

253965661 is an equidigital number, since it uses as much as digits as its factorization.

253965661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 867070.

The product of its digits is 291600, while the sum is 43.

The square root of 253965661 is about 15936.3001038510. The cubic root of 253965661 is about 633.2740125110.

The spelling of 253965661 in words is "two hundred fifty-three million, nine hundred sixty-five thousand, six hundred sixty-one".