251042081 has 2 divisors, whose sum is σ = 251042082. Its totient is φ = 251042080.

The previous prime is 251042063. The next prime is 251042137. The reversal of 251042081 is 180240152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 219513856 + 31528225 = 14816^2 + 5615^2 .

It is a cyclic number.

It is not a de Polignac number, because 251042081 - 2⁶ = 251042017 is a prime.

It is a super-2 number, since 2×251042081² = 126044252865621122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (251042021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125521040 + 125521041.

It is an arithmetic number, because the mean of its divisors is an integer number (125521041).

Almost surely, 2^251042081 is an apocalyptic number.

It is an amenable number.

251042081 is a deficient number, since it is larger than the sum of its proper divisors (1).

251042081 is an equidigital number, since it uses as much as digits as its factorization.

251042081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 251042081 is about 15844.3075266797. The cubic root of 251042081 is about 630.8346047791.

The spelling of 251042081 in words is "two hundred fifty-one million, forty-two thousand, eighty-one".