51816047 has 4 divisors (see below), whose sum is σ = 51848976. Its totient is φ = 51783120.

The previous prime is 51816029. The next prime is 51816049. The reversal of 51816047 is 74061815.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51816047 - 2¹⁸ = 51553903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51816049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13979 + ... + 17292.

It is an arithmetic number, because the mean of its divisors is an integer number (12962244).

Almost surely, 2^51816047 is an apocalyptic number.

51816047 is a deficient number, since it is larger than the sum of its proper divisors (32929).

51816047 is a wasteful number, since it uses less digits than its factorization.

51816047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32928.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 51816047 is about 7198.3364050314. The cubic root of 51816047 is about 372.8104632095.

The spelling of 51816047 in words is "fifty-one million, eight hundred sixteen thousand, forty-seven".