251442081 has 24 divisors (see below), whose sum is σ = 396972576. Its totient is φ = 152096640.

The previous prime is 251442071. The next prime is 251442083. The reversal of 251442081 is 180244152.

It is not a de Polignac number, because 251442081 - 2⁹ = 251441569 is a prime.

It is a super-2 number, since 2×251442081² = 126446240195221122, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (251442083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56566 + ... + 60848.

It is an arithmetic number, because the mean of its divisors is an integer number (16540524).

Almost surely, 2^251442081 is an apocalyptic number.

It is an amenable number.

251442081 is a deficient number, since it is larger than the sum of its proper divisors (145530495).

251442081 is a wasteful number, since it uses less digits than its factorization.

251442081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4893 (or 4890 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 27.

The square root of 251442081 is about 15856.9253324849. The cubic root of 251442081 is about 631.1694755174.

It can be divided in two parts, 25144 and 2081, that added together give a square (27225 = 165²).

The spelling of 251442081 in words is "two hundred fifty-one million, four hundred forty-two thousand, eighty-one".