56011661 has 2 divisors, whose sum is σ = 56011662. Its totient is φ = 56011660.

The previous prime is 56011621. The next prime is 56011667. The reversal of 56011661 is 16611065.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31696900 + 24314761 = 5630^2 + 4931^2 .

It is a cyclic number.

It is not a de Polignac number, because 56011661 - 2¹⁸ = 55749517 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 56011661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56011667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28005830 + 28005831.

It is an arithmetic number, because the mean of its divisors is an integer number (28005831).

Almost surely, 2^56011661 is an apocalyptic number.

It is an amenable number.

56011661 is a deficient number, since it is larger than the sum of its proper divisors (1).

56011661 is an equidigital number, since it uses as much as digits as its factorization.

56011661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 56011661 is about 7484.0938663274. The cubic root of 56011661 is about 382.6127902954.

It can be divided in two parts, 560 and 11661, that added together give a palindrome (12221).

The spelling of 56011661 in words is "fifty-six million, eleven thousand, six hundred sixty-one".