251989097 has 2 divisors, whose sum is σ = 251989098. Its totient is φ = 251989096.

The previous prime is 251989093. The next prime is 251989151. The reversal of 251989097 is 790989152.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 250398976 + 1590121 = 15824^2 + 1261^2 .

It is a cyclic number.

It is not a de Polignac number, because 251989097 - 2² = 251989093 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (251989093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125994548 + 125994549.

It is an arithmetic number, because the mean of its divisors is an integer number (125994549).

Almost surely, 2^251989097 is an apocalyptic number.

It is an amenable number.

251989097 is a deficient number, since it is larger than the sum of its proper divisors (1).

251989097 is an equidigital number, since it uses as much as digits as its factorization.

251989097 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 408240, while the sum is 50.

The square root of 251989097 is about 15874.1644504522. The cubic root of 251989097 is about 631.6268502072.

The spelling of 251989097 in words is "two hundred fifty-one million, nine hundred eighty-nine thousand, ninety-seven".