51191723 has 4 divisors (see below), whose sum is σ = 55845528. Its totient is φ = 46537920.

The previous prime is 51191717. The next prime is 51191747. The reversal of 51191723 is 32719115.

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

It is not a de Polignac number, because 51191723 - 2⁶ = 51191659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51191773) 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, 2326886 + ... + 2326907.

It is an arithmetic number, because the mean of its divisors is an integer number (13961382).

Almost surely, 2^51191723 is an apocalyptic number.

51191723 is a deficient number, since it is larger than the sum of its proper divisors (4653805).

51191723 is a wasteful number, since it uses less digits than its factorization.

51191723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4653804.

The product of its digits is 1890, while the sum is 29.

The square root of 51191723 is about 7154.8391316647. The cubic root of 51191723 is about 371.3070960113.

The spelling of 51191723 in words is "fifty-one million, one hundred ninety-one thousand, seven hundred twenty-three".