51031291 has 2 divisors, whose sum is σ = 51031292. Its totient is φ = 51031290.

The previous prime is 51031261. The next prime is 51031313. The reversal of 51031291 is 19213015.

It is an a-pointer prime, because the next prime (51031313) can be obtained adding 51031291 to its sum of digits (22).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51031291 - 2⁷ = 51031163 is a prime.

It is a super-2 number, since 2×51031291² = 5208385322253362, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51031231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25515645 + 25515646.

It is an arithmetic number, because the mean of its divisors is an integer number (25515646).

Almost surely, 2^51031291 is an apocalyptic number.

51031291 is a deficient number, since it is larger than the sum of its proper divisors (1).

51031291 is an equidigital number, since it uses as much as digits as its factorization.

51031291 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 270, while the sum is 22.

The square root of 51031291 is about 7143.6189008093. The cubic root of 51031291 is about 370.9188048690.

The spelling of 51031291 in words is "fifty-one million, thirty-one thousand, two hundred ninety-one".