253616661 has 6 divisors (see below), whose sum is σ = 366335190. Its totient is φ = 169077768.

The previous prime is 253616651. The next prime is 253616663. The reversal of 253616661 is 166616352.

It can be written as a sum of positive squares in only one way, i.e., 177822225 + 75794436 = 13335^2 + 8706^2 .

It is not a de Polignac number, because 253616661 - 2¹⁹ = 253092373 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253616663) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14089806 + ... + 14089823.

It is an arithmetic number, because the mean of its divisors is an integer number (61055865).

Almost surely, 2^253616661 is an apocalyptic number.

It is an amenable number.

253616661 is a deficient number, since it is larger than the sum of its proper divisors (112718529).

253616661 is a wasteful number, since it uses less digits than its factorization.

253616661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28179635 (or 28179632 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The square root of 253616661 is about 15925.3464954456. The cubic root of 253616661 is about 632.9837974934.

The spelling of 253616661 in words is "two hundred fifty-three million, six hundred sixteen thousand, six hundred sixty-one".