51821767 has 2 divisors, whose sum is σ = 51821768. Its totient is φ = 51821766.

The previous prime is 51821747. The next prime is 51821771. The reversal of 51821767 is 76712815.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51821767 - 2⁷ = 51821639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51821717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25910883 + 25910884.

It is an arithmetic number, because the mean of its divisors is an integer number (25910884).

Almost surely, 2^51821767 is an apocalyptic number.

51821767 is a deficient number, since it is larger than the sum of its proper divisors (1).

51821767 is an equidigital number, since it uses as much as digits as its factorization.

51821767 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23520, while the sum is 37.

The square root of 51821767 is about 7198.7337080906. The cubic root of 51821767 is about 372.8241809508.

The spelling of 51821767 in words is "fifty-one million, eight hundred twenty-one thousand, seven hundred sixty-seven".