657200000020 has 36 divisors (see below), whose sum is σ = 1387874594484. Its totient is φ = 261411141760.

The previous prime is 657199999999. The next prime is 657200000123. The reversal of 657200000020 is 20000002756.

It can be written as a sum of positive squares in 2 ways, for example, as 190134369936 + 467065630084 = 436044^2 + 683422^2 .

It is a junction number, because it is equal to n+sod(n) for n = 657199999937 and 657200000000.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 128040 + ... + 1153600.

It is an arithmetic number, because the mean of its divisors is an integer number (38552072069).

Almost surely, 2^657200000020 is an apocalyptic number.

It is an amenable number.

657200000020 is an abundant number, since it is smaller than the sum of its proper divisors (730674594464).

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

657200000020 is a wasteful number, since it uses less digits than its factorization.

657200000020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1025928 (or 1025747 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 22.

Adding to 657200000020 its reverse (20000002756), we get a palindrome (677200002776).

The spelling of 657200000020 in words is "six hundred fifty-seven billion, two hundred million, twenty", and thus it is an aban number.