257551563 has 4 divisors (see below), whose sum is σ = 343402088. Its totient is φ = 171701040.

The previous prime is 257551559. The next prime is 257551583. The reversal of 257551563 is 365155752.

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

It is not a de Polignac number, because 257551563 - 2² = 257551559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257551583) 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, 42925258 + ... + 42925263.

It is an arithmetic number, because the mean of its divisors is an integer number (85850522).

Almost surely, 2^257551563 is an apocalyptic number.

257551563 is a deficient number, since it is larger than the sum of its proper divisors (85850525).

257551563 is an equidigital number, since it uses as much as digits as its factorization.

257551563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85850524.

The product of its digits is 157500, while the sum is 39.

The square root of 257551563 is about 16048.4130991198. The cubic root of 257551563 is about 636.2406257923.

The spelling of 257551563 in words is "two hundred fifty-seven million, five hundred fifty-one thousand, five hundred sixty-three".