51557189 has 2 divisors, whose sum is σ = 51557190. Its totient is φ = 51557188.

The previous prime is 51557171. The next prime is 51557221. The reversal of 51557189 is 98175515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35796289 + 15760900 = 5983^2 + 3970^2 .

It is a cyclic number.

It is not a de Polignac number, because 51557189 - 2⁸ = 51556933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51554189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25778594 + 25778595.

It is an arithmetic number, because the mean of its divisors is an integer number (25778595).

Almost surely, 2^51557189 is an apocalyptic number.

It is an amenable number.

51557189 is a deficient number, since it is larger than the sum of its proper divisors (1).

51557189 is an equidigital number, since it uses as much as digits as its factorization.

51557189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63000, while the sum is 41.

The square root of 51557189 is about 7180.3334880770. Note that the first 3 decimals coincide. The cubic root of 51557189 is about 372.1886087350.

The spelling of 51557189 in words is "fifty-one million, five hundred fifty-seven thousand, one hundred eighty-nine".