251140649 has 2 divisors, whose sum is σ = 251140650. Its totient is φ = 251140648.

The previous prime is 251140619. The next prime is 251140691. The reversal of 251140649 is 946041152.

251140649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 242020249 + 9120400 = 15557^2 + 3020^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251140649 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (251140619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125570324 + 125570325.

It is an arithmetic number, because the mean of its divisors is an integer number (125570325).

Almost surely, 2^251140649 is an apocalyptic number.

It is an amenable number.

251140649 is a deficient number, since it is larger than the sum of its proper divisors (1).

251140649 is an equidigital number, since it uses as much as digits as its factorization.

251140649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 251140649 is about 15847.4177391776. The cubic root of 251140649 is about 630.9171566350.

The spelling of 251140649 in words is "two hundred fifty-one million, one hundred forty thousand, six hundred forty-nine".