57216555 has 24 divisors (see below), whose sum is σ = 108192240. Its totient is φ = 27741120.

The previous prime is 57216553. The next prime is 57216559. The reversal of 57216555 is 55561275.

It is a happy number.

57216555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 57216555 - 2¹ = 57216553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (57216553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57300 + ... + 58289.

It is an arithmetic number, because the mean of its divisors is an integer number (4508010).

Almost surely, 2^57216555 is an apocalyptic number.

57216555 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

57216555 is a deficient number, since it is larger than the sum of its proper divisors (50975685).

57216555 is a wasteful number, since it uses less digits than its factorization.

57216555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115611 (or 115608 counting only the distinct ones).

The product of its digits is 52500, while the sum is 36.

The square root of 57216555 is about 7564.1625445253. The cubic root of 57216555 is about 385.3368727467.

It can be divided in two parts, 57 and 216555, that added together give a palindrome (216612).

The spelling of 57216555 in words is "fifty-seven million, two hundred sixteen thousand, five hundred fifty-five".