55999961 has 2 divisors, whose sum is σ = 55999962. Its totient is φ = 55999960.

The previous prime is 55999913. The next prime is 55999969. The reversal of 55999961 is 16999955.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29539225 + 26460736 = 5435^2 + 5144^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55999961 is a prime.

It is not a weakly prime, because it can be changed into another prime (55999969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27999980 + 27999981.

It is an arithmetic number, because the mean of its divisors is an integer number (27999981).

Almost surely, 2^55999961 is an apocalyptic number.

It is an amenable number.

55999961 is a deficient number, since it is larger than the sum of its proper divisors (1).

55999961 is an equidigital number, since it uses as much as digits as its factorization.

55999961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 984150, while the sum is 53.

The square root of 55999961 is about 7483.3121677503. The cubic root of 55999961 is about 382.5861477398.

The spelling of 55999961 in words is "fifty-five million, nine hundred ninety-nine thousand, nine hundred sixty-one".