251320669 has 2 divisors, whose sum is σ = 251320670. Its totient is φ = 251320668.

The previous prime is 251320607. The next prime is 251320723. The reversal of 251320669 is 966023152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 249324100 + 1996569 = 15790^2 + 1413^2 .

It is a cyclic number.

It is not a de Polignac number, because 251320669 - 2¹¹ = 251318621 is a prime.

It is a super-2 number, since 2×251320669² = 126324157333215122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (251380669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125660334 + 125660335.

It is an arithmetic number, because the mean of its divisors is an integer number (125660335).

Almost surely, 2^251320669 is an apocalyptic number.

It is an amenable number.

251320669 is a deficient number, since it is larger than the sum of its proper divisors (1).

251320669 is an equidigital number, since it uses as much as digits as its factorization.

251320669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 251320669 is about 15853.0965114075. The cubic root of 251320669 is about 631.0678697645.

The spelling of 251320669 in words is "two hundred fifty-one million, three hundred twenty thousand, six hundred sixty-nine".