657205902242 has 18 divisors (see below), whose sum is σ = 989951741649. Its totient is φ = 327227750760.

The previous prime is 657205902169. The next prime is 657205902247. The reversal of 657205902242 is 242209502756.

It can be written as a sum of positive squares in 2 ways, for example, as 491539807801 + 165666094441 = 701099^2 + 407021^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=573239.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 657205902193 and 657205902202.

It is not an unprimeable number, because it can be changed into a prime (657205902247) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 308401517 + ... + 308403647.

Almost surely, 2^657205902242 is an apocalyptic number.

657205902242 is a deficient number, since it is larger than the sum of its proper divisors (332745839407).

657205902242 is an frugal number, since it uses more digits than its factorization.

657205902242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4802 (or 2402 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 44.

The spelling of 657205902242 in words is "six hundred fifty-seven billion, two hundred five million, nine hundred two thousand, two hundred forty-two".