57220020 has 360 divisors, whose sum is σ = 223201440. Its totient is φ = 12130560.

The previous prime is 57220003. The next prime is 57220027. The reversal of 57220020 is 2002275.

57220020 = 353² + 354² + ... + 599².

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 57219975 and 57220002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (57220027) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 3011571 + ... + 3011589.

It is an arithmetic number, because the mean of its divisors is an integer number (620004).

Almost surely, 2^57220020 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 57220020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111600720).

57220020 is an abundant number, since it is smaller than the sum of its proper divisors (165981420).

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

57220020 is a wasteful number, since it uses less digits than its factorization.

57220020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 18.

The square root of 57220020 is about 7564.3915816145. The cubic root of 57220020 is about 385.3446511790.

Adding to 57220020 its reverse (2002275), we get a palindrome (59222295).

The spelling of 57220020 in words is "fifty-seven million, two hundred twenty thousand, twenty".