1657231 has 2 divisors, whose sum is σ = 1657232. Its totient is φ = 1657230.

The previous prime is 1657213. The next prime is 1657247. The reversal of 1657231 is 1327561.

Together with previous prime (1657213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is an emirp because it is prime and its reverse (1327561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1657231 - 2⁹ = 1656719 is a prime.

It is a super-2 number, since 2×1657231² = 5492829174722, which contains 22 as substring.

1657231 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1657196 and 1657205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1657631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 828615 + 828616.

It is an arithmetic number, because the mean of its divisors is an integer number (828616).

2^1657231 is an apocalyptic number.

1657231 is a deficient number, since it is larger than the sum of its proper divisors (1).

1657231 is an equidigital number, since it uses as much as digits as its factorization.

1657231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1260, while the sum is 25.

The square root of 1657231 is about 1287.3348437761. The cubic root of 1657231 is about 118.3389421838.

It can be divided in two parts, 165 and 7231, that added together give a square (7396 = 86²).

The spelling of 1657231 in words is "one million, six hundred fifty-seven thousand, two hundred thirty-one".