51545639 has 2 divisors, whose sum is σ = 51545640. Its totient is φ = 51545638.

The previous prime is 51545609. The next prime is 51545647. The reversal of 51545639 is 93654515.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51545639 - 2¹⁶ = 51480103 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51545609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25772819 + 25772820.

It is an arithmetic number, because the mean of its divisors is an integer number (25772820).

Almost surely, 2^51545639 is an apocalyptic number.

51545639 is a deficient number, since it is larger than the sum of its proper divisors (1).

51545639 is an equidigital number, since it uses as much as digits as its factorization.

51545639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81000, while the sum is 38.

The square root of 51545639 is about 7179.5291628351. The cubic root of 51545639 is about 372.1608137138.

The spelling of 51545639 in words is "fifty-one million, five hundred forty-five thousand, six hundred thirty-nine".