51017947 has 2 divisors, whose sum is σ = 51017948. Its totient is φ = 51017946.

The previous prime is 51017929. The next prime is 51017951. The reversal of 51017947 is 74971015.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51017947 is a prime.

It is equal to p_3058486 and since 51017947 and 3058486 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (51017977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25508973 + 25508974.

It is an arithmetic number, because the mean of its divisors is an integer number (25508974).

Almost surely, 2^51017947 is an apocalyptic number.

51017947 is a deficient number, since it is larger than the sum of its proper divisors (1).

51017947 is an equidigital number, since it uses as much as digits as its factorization.

51017947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8820, while the sum is 34.

The square root of 51017947 is about 7142.6848593509. The cubic root of 51017947 is about 370.8864719486.

The spelling of 51017947 in words is "fifty-one million, seventeen thousand, nine hundred forty-seven".