51851869 has 2 divisors, whose sum is σ = 51851870. Its totient is φ = 51851868.

The previous prime is 51851803. The next prime is 51851927. The reversal of 51851869 is 96815815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45024100 + 6827769 = 6710^2 + 2613^2 .

It is a cyclic number.

It is not a de Polignac number, because 51851869 - 2⁹ = 51851357 is a prime.

It is a super-2 number, since 2×51851869² = 5377232637586322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51831869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25925934 + 25925935.

It is an arithmetic number, because the mean of its divisors is an integer number (25925935).

Almost surely, 2^51851869 is an apocalyptic number.

It is an amenable number.

51851869 is a deficient number, since it is larger than the sum of its proper divisors (1).

51851869 is an equidigital number, since it uses as much as digits as its factorization.

51851869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86400, while the sum is 43.

The square root of 51851869 is about 7200.8241889384. The cubic root of 51851869 is about 372.8963551345.

The spelling of 51851869 in words is "fifty-one million, eight hundred fifty-one thousand, eight hundred sixty-nine".