257720201 has 4 divisors (see below), whose sum is σ = 262088400. Its totient is φ = 253352004.

The previous prime is 257720191. The next prime is 257720209. The reversal of 257720201 is 102027752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 257720201 - 2²² = 253525897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257720209) 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, 2184011 + ... + 2184128.

It is an arithmetic number, because the mean of its divisors is an integer number (65522100).

Almost surely, 2^257720201 is an apocalyptic number.

It is an amenable number.

257720201 is a deficient number, since it is larger than the sum of its proper divisors (4368199).

257720201 is an equidigital number, since it uses as much as digits as its factorization.

257720201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4368198.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 257720201 is about 16053.6662790778. Note that the first 3 decimals coincide. The cubic root of 257720201 is about 636.3794600462.

Adding to 257720201 its reverse (102027752), we get a palindrome (359747953).

The spelling of 257720201 in words is "two hundred fifty-seven million, seven hundred twenty thousand, two hundred one".