51864779 has 2 divisors, whose sum is σ = 51864780. Its totient is φ = 51864778.

The previous prime is 51864749. The next prime is 51864803. The reversal of 51864779 is 97746815.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51864779 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51864749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25932389 + 25932390.

It is an arithmetic number, because the mean of its divisors is an integer number (25932390).

Almost surely, 2^51864779 is an apocalyptic number.

51864779 is a deficient number, since it is larger than the sum of its proper divisors (1).

51864779 is an equidigital number, since it uses as much as digits as its factorization.

51864779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 423360, while the sum is 47.

The square root of 51864779 is about 7201.7205583110. The cubic root of 51864779 is about 372.9273002901.

The spelling of 51864779 in words is "fifty-one million, eight hundred sixty-four thousand, seven hundred seventy-nine".