57213440 has 40 divisors (see below), whose sum is σ = 137184300. Its totient is φ = 22884352.

The previous prime is 57213439. The next prime is 57213451. The reversal of 57213440 is 4431275.

It can be written as a sum of positive squares in 2 ways, for example, as 53465344 + 3748096 = 7312^2 + 1936^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8615 + ... + 13734.

Almost surely, 2^57213440 is an apocalyptic number.

It is an amenable number.

57213440 is an abundant number, since it is smaller than the sum of its proper divisors (79970860).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

57213440 is an equidigital number, since it uses as much as digits as its factorization.

57213440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22372 (or 22356 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 57213440 is about 7563.9566365759. The cubic root of 57213440 is about 385.3298797465.

The spelling of 57213440 in words is "fifty-seven million, two hundred thirteen thousand, four hundred forty".