251010161 has 2 divisors, whose sum is σ = 251010162. Its totient is φ = 251010160.

The previous prime is 251010143. The next prime is 251010163. The reversal of 251010161 is 161010152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 241615936 + 9394225 = 15544^2 + 3065^2 .

It is a cyclic number.

It is not a de Polignac number, because 251010161 - 2¹⁴ = 250993777 is a prime.

It is a super-2 number, since 2×251010161² = 126012201850491842, which contains 22 as substring.

Together with 251010163, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (251010163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125505080 + 125505081.

It is an arithmetic number, because the mean of its divisors is an integer number (125505081).

Almost surely, 2^251010161 is an apocalyptic number.

It is an amenable number.

251010161 is a deficient number, since it is larger than the sum of its proper divisors (1).

251010161 is an equidigital number, since it uses as much as digits as its factorization.

251010161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60, while the sum is 17.

The square root of 251010161 is about 15843.3001928260. The cubic root of 251010161 is about 630.8078667730.

Subtracting from 251010161 its reverse (161010152), we obtain a palindrome (90000009).

The spelling of 251010161 in words is "two hundred fifty-one million, ten thousand, one hundred sixty-one".