51891569 has 2 divisors, whose sum is σ = 51891570. Its totient is φ = 51891568.

The previous prime is 51891533. The next prime is 51891571. The reversal of 51891569 is 96519815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50580544 + 1311025 = 7112^2 + 1145^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51891569 is a prime.

It is a super-2 number, since 2×51891569² = 5385469866563522, which contains 22 as substring.

Together with 51891571, 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 (51891529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25945784 + 25945785.

It is an arithmetic number, because the mean of its divisors is an integer number (25945785).

Almost surely, 2^51891569 is an apocalyptic number.

It is an amenable number.

51891569 is a deficient number, since it is larger than the sum of its proper divisors (1).

51891569 is an equidigital number, since it uses as much as digits as its factorization.

51891569 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 97200, while the sum is 44.

The square root of 51891569 is about 7203.5802903834. The cubic root of 51891569 is about 372.9914993019.

The spelling of 51891569 in words is "fifty-one million, eight hundred ninety-one thousand, five hundred sixty-nine".