51831869 has 2 divisors, whose sum is σ = 51831870. Its totient is φ = 51831868.

The previous prime is 51831847. The next prime is 51831877. The reversal of 51831869 is 96813815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30946969 + 20884900 = 5563^2 + 4570^2 .

It is a cyclic number.

It is not a de Polignac number, because 51831869 - 2²⁴ = 35054653 is a prime.

It is a super-2 number, since 2×51831869² = 5373085288066322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51831809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25915934 + 25915935.

It is an arithmetic number, because the mean of its divisors is an integer number (25915935).

Almost surely, 2^51831869 is an apocalyptic number.

It is an amenable number.

51831869 is a deficient number, since it is larger than the sum of its proper divisors (1).

51831869 is an equidigital number, since it uses as much as digits as its factorization.

51831869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 41.

The square root of 51831869 is about 7199.4353250793. The cubic root of 51831869 is about 372.8484051678.

The spelling of 51831869 in words is "fifty-one million, eight hundred thirty-one thousand, eight hundred sixty-nine".