251015131 has 2 divisors, whose sum is σ = 251015132. Its totient is φ = 251015130.

The previous prime is 251015129. The next prime is 251015147. The reversal of 251015131 is 131510152.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 251015131 - 2¹ = 251015129 is a prime.

It is a super-2 number, since 2×251015131² = 126017191981894322, which contains 22 as substring.

Together with 251015129, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 251015099 and 251015108.

It is not a weakly prime, because it can be changed into another prime (251015731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 125507565 + 125507566.

It is an arithmetic number, because the mean of its divisors is an integer number (125507566).

Almost surely, 2^251015131 is an apocalyptic number.

251015131 is a deficient number, since it is larger than the sum of its proper divisors (1).

251015131 is an equidigital number, since it uses as much as digits as its factorization.

251015131 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 150, while the sum is 19.

The square root of 251015131 is about 15843.4570406840. The cubic root of 251015131 is about 630.8120300765.

Adding to 251015131 its reverse (131510152), we get a palindrome (382525283).

The spelling of 251015131 in words is "two hundred fifty-one million, fifteen thousand, one hundred thirty-one".