251140009 has 2 divisors, whose sum is σ = 251140010. Its totient is φ = 251140008.

The previous prime is 251139983. The next prime is 251140027. The reversal of 251140009 is 900041152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 135792409 + 115347600 = 11653^2 + 10740^2 .

It is a cyclic number.

It is not a de Polignac number, because 251140009 - 2⁷ = 251139881 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (251140069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125570004 + 125570005.

It is an arithmetic number, because the mean of its divisors is an integer number (125570005).

Almost surely, 2^251140009 is an apocalyptic number.

It is an amenable number.

251140009 is a deficient number, since it is larger than the sum of its proper divisors (1).

251140009 is an equidigital number, since it uses as much as digits as its factorization.

251140009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 251140009 is about 15847.3975466005. The cubic root of 251140009 is about 630.9166206972.

The spelling of 251140009 in words is "two hundred fifty-one million, one hundred forty thousand, nine".