55709557 has 2 divisors, whose sum is σ = 55709558. Its totient is φ = 55709556.

The previous prime is 55709513. The next prime is 55709567. The reversal of 55709557 is 75590755.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46703556 + 9006001 = 6834^2 + 3001^2 .

It is a cyclic number.

It is not a de Polignac number, because 55709557 - 2¹⁹ = 55185269 is a prime.

It is a super-2 number, since 2×55709557² = 6207109482272498, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55709567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27854778 + 27854779.

It is an arithmetic number, because the mean of its divisors is an integer number (27854779).

Almost surely, 2^55709557 is an apocalyptic number.

It is an amenable number.

55709557 is a deficient number, since it is larger than the sum of its proper divisors (1).

55709557 is an equidigital number, since it uses as much as digits as its factorization.

55709557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 275625, while the sum is 43.

The square root of 55709557 is about 7463.8835065936. The cubic root of 55709557 is about 381.9236641963.

The spelling of 55709557 in words is "fifty-five million, seven hundred nine thousand, five hundred fifty-seven".