257163997 has 4 divisors (see below), whose sum is σ = 258469596. Its totient is φ = 255858400.

The previous prime is 257163979. The next prime is 257164001. The reversal of 257163997 is 799361752.

257163997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 241211961 + 15952036 = 15531^2 + 3994^2 .

It is a cyclic number.

It is not a de Polignac number, because 257163997 - 2¹⁵ = 257131229 is a prime.

It is a super-2 number, since 2×257163997² = 132266642706032018, which contains 22 as substring.

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 257163997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257163937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 652504 + ... + 652897.

It is an arithmetic number, because the mean of its divisors is an integer number (64617399).

Almost surely, 2^257163997 is an apocalyptic number.

It is an amenable number.

257163997 is a deficient number, since it is larger than the sum of its proper divisors (1305599).

257163997 is a wasteful number, since it uses less digits than its factorization.

257163997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1305598.

The product of its digits is 714420, while the sum is 49.

The square root of 257163997 is about 16036.3336520540. Note that the first 3 decimals coincide. The cubic root of 257163997 is about 635.9213252958.

The spelling of 257163997 in words is "two hundred fifty-seven million, one hundred sixty-three thousand, nine hundred ninety-seven".