51113031391 has 2 divisors, whose sum is σ = 51113031392. Its totient is φ = 51113031390.

The previous prime is 51113031379. The next prime is 51113031439. The reversal of 51113031391 is 19313031115.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51113031391 - 2²³ = 51104642783 is a prime.

It is a super-2 number, since 2×51113031391² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51113031331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25556515695 + 25556515696.

It is an arithmetic number, because the mean of its divisors is an integer number (25556515696).

Almost surely, 2^51113031391 is an apocalyptic number.

51113031391 is a deficient number, since it is larger than the sum of its proper divisors (1).

51113031391 is an equidigital number, since it uses as much as digits as its factorization.

51113031391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1215, while the sum is 28.

The spelling of 51113031391 in words is "fifty-one billion, one hundred thirteen million, thirty-one thousand, three hundred ninety-one".