51399923 has 2 divisors, whose sum is σ = 51399924. Its totient is φ = 51399922.

The previous prime is 51399899. The next prime is 51399941. The reversal of 51399923 is 32999315.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51399923 - 2²² = 47205619 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (51392923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25699961 + 25699962.

It is an arithmetic number, because the mean of its divisors is an integer number (25699962).

Almost surely, 2^51399923 is an apocalyptic number.

51399923 is a deficient number, since it is larger than the sum of its proper divisors (1).

51399923 is an equidigital number, since it uses as much as digits as its factorization.

51399923 is an evil number, because the sum of its binary digits is even.

The product of its digits is 65610, while the sum is 41.

The square root of 51399923 is about 7169.3739615116. The cubic root of 51399923 is about 371.8097916688.

The spelling of 51399923 in words is "fifty-one million, three hundred ninety-nine thousand, nine hundred twenty-three".