253781 has 4 divisors (see below), whose sum is σ = 276864. Its totient is φ = 230700.

The previous prime is 253777. The next prime is 253787. The reversal of 253781 is 187352.

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 253781 - 2² = 253777 is a prime.

It is a super-2 number, since 2×253781² = 128809591922, 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 253781.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 253781.

It is not an unprimeable number, because it can be changed into a prime (253787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11525 + ... + 11546.

It is an arithmetic number, because the mean of its divisors is an integer number (69216).

2²⁵³⁷⁸¹ is an apocalyptic number.

It is an amenable number.

253781 is a deficient number, since it is larger than the sum of its proper divisors (23083).

253781 is a wasteful number, since it uses less digits than its factorization.

253781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23082.

The product of its digits is 1680, while the sum is 26.

The square root of 253781 is about 503.7668111339. The cubic root of 253781 is about 63.3120488650.

The spelling of 253781 in words is "two hundred fifty-three thousand, seven hundred eighty-one".