51605189 has 2 divisors, whose sum is σ = 51605190. Its totient is φ = 51605188.

The previous prime is 51605161. The next prime is 51605221. The reversal of 51605189 is 98150615.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47472100 + 4133089 = 6890^2 + 2033^2 .

It is a cyclic number.

It is not a de Polignac number, because 51605189 - 2²⁰ = 50556613 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51605789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25802594 + 25802595.

It is an arithmetic number, because the mean of its divisors is an integer number (25802595).

Almost surely, 2^51605189 is an apocalyptic number.

It is an amenable number.

51605189 is a deficient number, since it is larger than the sum of its proper divisors (1).

51605189 is an equidigital number, since it uses as much as digits as its factorization.

51605189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10800, while the sum is 35.

The square root of 51605189 is about 7183.6751736141. The cubic root of 51605189 is about 372.3040760589.

The spelling of 51605189 in words is "fifty-one million, six hundred five thousand, one hundred eighty-nine".