55085257 has 4 divisors (see below), whose sum is σ = 55988356. Its totient is φ = 54182160.

The previous prime is 55085249. The next prime is 55085309. The reversal of 55085257 is 75258055.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24049216 + 31036041 = 4904^2 + 5571^2 .

It is a cyclic number.

It is not a de Polignac number, because 55085257 - 2³ = 55085249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55085227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 451458 + ... + 451579.

It is an arithmetic number, because the mean of its divisors is an integer number (13997089).

Almost surely, 2^55085257 is an apocalyptic number.

It is an amenable number.

55085257 is a deficient number, since it is larger than the sum of its proper divisors (903099).

55085257 is an equidigital number, since it uses as much as digits as its factorization.

55085257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 903098.

The product of its (nonzero) digits is 70000, while the sum is 37.

The square root of 55085257 is about 7421.9442870450. The cubic root of 55085257 is about 380.4916466400.

The spelling of 55085257 in words is "fifty-five million, eighty-five thousand, two hundred fifty-seven".