51133391 has 2 divisors, whose sum is σ = 51133392. Its totient is φ = 51133390.

The previous prime is 51133367. The next prime is 51133417. The reversal of 51133391 is 19333115.

It is an a-pointer prime, because the next prime (51133417) can be obtained adding 51133391 to its sum of digits (26).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51133391 is a prime.

It is a super-2 number, since 2×51133391² = 5229247350317762, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51133391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51133591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25566695 + 25566696.

It is an arithmetic number, because the mean of its divisors is an integer number (25566696).

Almost surely, 2^51133391 is an apocalyptic number.

51133391 is a deficient number, since it is larger than the sum of its proper divisors (1).

51133391 is an equidigital number, since it uses as much as digits as its factorization.

51133391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1215, while the sum is 26.

The square root of 51133391 is about 7150.7615678332. The cubic root of 51133391 is about 371.1660099387.

The spelling of 51133391 in words is "fifty-one million, one hundred thirty-three thousand, three hundred ninety-one".