55956557 has 2 divisors, whose sum is σ = 55956558. Its totient is φ = 55956556.

The previous prime is 55956553. The next prime is 55956559. The reversal of 55956557 is 75565955.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38700841 + 17255716 = 6221^2 + 4154^2 .

It is a cyclic number.

It is not a de Polignac number, because 55956557 - 2² = 55956553 is a prime.

It is a super-2 number, since 2×55956557² = 6262272542588498, which contains 22 as substring.

Together with 55956559, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55956553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27978278 + 27978279.

It is an arithmetic number, because the mean of its divisors is an integer number (27978279).

Almost surely, 2^55956557 is an apocalyptic number.

It is an amenable number.

55956557 is a deficient number, since it is larger than the sum of its proper divisors (1).

55956557 is an equidigital number, since it uses as much as digits as its factorization.

55956557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1181250, while the sum is 47.

The square root of 55956557 is about 7480.4115528492. The cubic root of 55956557 is about 382.4872782589.

The spelling of 55956557 in words is "fifty-five million, nine hundred fifty-six thousand, five hundred fifty-seven".