51999971 has 2 divisors, whose sum is σ = 51999972. Its totient is φ = 51999970.

The previous prime is 51999919. The next prime is 52000007. The reversal of 51999971 is 17999915.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51999971 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 (51999071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25999985 + 25999986.

It is an arithmetic number, because the mean of its divisors is an integer number (25999986).

Almost surely, 2^51999971 is an apocalyptic number.

51999971 is a deficient number, since it is larger than the sum of its proper divisors (1).

51999971 is an equidigital number, since it uses as much as digits as its factorization.

51999971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 229635, while the sum is 50.

The square root of 51999971 is about 7211.1005401395. The cubic root of 51999971 is about 373.2510462953.

The spelling of 51999971 in words is "fifty-one million, nine hundred ninety-nine thousand, nine hundred seventy-one".