251581441 has 4 divisors (see below), whose sum is σ = 251741952. Its totient is φ = 251420932.

The previous prime is 251581423. The next prime is 251581481. The reversal of 251581441 is 144185152.

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 251581441 - 2⁹ = 251580929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251581481) 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, 77881 + ... + 81046.

It is an arithmetic number, because the mean of its divisors is an integer number (62935488).

Almost surely, 2^251581441 is an apocalyptic number.

It is an amenable number.

251581441 is a deficient number, since it is larger than the sum of its proper divisors (160511).

251581441 is a wasteful number, since it uses less digits than its factorization.

251581441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160510.

The product of its digits is 6400, while the sum is 31.

The square root of 251581441 is about 15861.3190182910. The cubic root of 251581441 is about 631.2860610579.

The spelling of 251581441 in words is "two hundred fifty-one million, five hundred eighty-one thousand, four hundred forty-one".