51666539 has 2 divisors, whose sum is σ = 51666540. Its totient is φ = 51666538.

The previous prime is 51666499. The next prime is 51666557. The reversal of 51666539 is 93566615.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51666539 - 2⁸ = 51666283 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 51666496 and 51666505.

It is not a weakly prime, because it can be changed into another prime (51666239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25833269 + 25833270.

It is an arithmetic number, because the mean of its divisors is an integer number (25833270).

Almost surely, 2^51666539 is an apocalyptic number.

51666539 is a deficient number, since it is larger than the sum of its proper divisors (1).

51666539 is an equidigital number, since it uses as much as digits as its factorization.

51666539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145800, while the sum is 41.

The square root of 51666539 is about 7187.9440036773. The cubic root of 51666539 is about 372.4515535391.

The spelling of 51666539 in words is "fifty-one million, six hundred sixty-six thousand, five hundred thirty-nine".