641257 has 8 divisors (see below), whose sum is σ = 690336. Its totient is φ = 593472.

The previous prime is 641239. The next prime is 641261. The reversal of 641257 is 752146.

641257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 641257 - 2⁷ = 641129 is a prime.

It is a super-2 number, since 2×641257² = 822421080098, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 858 + ... + 1420.

It is an arithmetic number, because the mean of its divisors is an integer number (86292).

2⁶⁴¹²⁵⁷ is an apocalyptic number.

641257 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

It is an amenable number.

641257 is a deficient number, since it is larger than the sum of its proper divisors (49079).

641257 is a wasteful number, since it uses less digits than its factorization.

641257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 647.

The product of its digits is 1680, while the sum is 25.

The square root of 641257 is about 800.7852396242. The cubic root of 641257 is about 86.2337699630.

Subtracting 641257 from its reverse (752146), we obtain a square (110889 = 333²).

It can be divided in two parts, 641 and 257, that added together give a palindrome (898).

The spelling of 641257 in words is "six hundred forty-one thousand, two hundred fifty-seven".