257798892121 has 9 divisors (see below), whose sum is σ = 273864739999. Its totient is φ = 242626127584.

The previous prime is 257798892103. The next prime is 257798892151. The reversal of 257798892121 is 121298897752.

The square root of 257798892121 is 507739.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 200708480025 + 57090412096 = 448005^2 + 238936^2 .

It is not a de Polignac number, because 257798892121 - 2²³ = 257790503513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 257798892121.

It is not an unprimeable number, because it can be changed into a prime (257798892151) 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, 8616630 + ... + 8646496.

Almost surely, 2^257798892121 is an apocalyptic number.

257798892121 is the 507739-th square number.

257798892121 is the 253870-th centered octagonal number.

It is an amenable number.

257798892121 is a deficient number, since it is larger than the sum of its proper divisors (16065847878).

257798892121 is an frugal number, since it uses more digits than its factorization.

257798892121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59768 (or 29884 counting only the distinct ones).

The product of its digits is 10160640, while the sum is 61.

The spelling of 257798892121 in words is "two hundred fifty-seven billion, seven hundred ninety-eight million, eight hundred ninety-two thousand, one hundred twenty-one".