57213640 has 48 divisors (see below), whose sum is σ = 141509340. Its totient is φ = 20803200.

The previous prime is 57213623. The next prime is 57213661. The reversal of 57213640 is 4631275.

It can be written as a sum of positive squares in 2 ways, for example, as 53027524 + 4186116 = 7282^2 + 2046^2 .

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 57213599 and 57213608.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1071 + ... + 10750.

Almost surely, 2^57213640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 57213640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70754670).

57213640 is an abundant number, since it is smaller than the sum of its proper divisors (84295700).

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

57213640 is a wasteful number, since it uses less digits than its factorization.

57213640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11854 (or 11839 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 57213640 is about 7563.9698571583. The cubic root of 57213640 is about 385.3303287429.

The spelling of 57213640 in words is "fifty-seven million, two hundred thirteen thousand, six hundred forty".