55857121 has 4 divisors (see below), whose sum is σ = 59142852. Its totient is φ = 52571392.

The previous prime is 55857107. The next prime is 55857157. The reversal of 55857121 is 12175855.

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 38750625 + 17106496 = 6225^2 + 4136^2 .

It is a cyclic number.

It is not a de Polignac number, because 55857121 - 2⁵ = 55857089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55857181) 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, 1642840 + ... + 1642873.

It is an arithmetic number, because the mean of its divisors is an integer number (14785713).

Almost surely, 2^55857121 is an apocalyptic number.

It is an amenable number.

55857121 is a deficient number, since it is larger than the sum of its proper divisors (3285731).

55857121 is a wasteful number, since it uses less digits than its factorization.

55857121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3285730.

The product of its digits is 14000, while the sum is 34.

The square root of 55857121 is about 7473.7621717579. The cubic root of 55857121 is about 382.2605812294.

The spelling of 55857121 in words is "fifty-five million, eight hundred fifty-seven thousand, one hundred twenty-one".