51155723 has 4 divisors (see below), whose sum is σ = 51499200. Its totient is φ = 50812248.

The previous prime is 51155711. The next prime is 51155729. The reversal of 51155723 is 32755115.

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 51155723 - 2²⁴ = 34378507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51155729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171515 + ... + 171812.

It is an arithmetic number, because the mean of its divisors is an integer number (12874800).

Almost surely, 2^51155723 is an apocalyptic number.

51155723 is a deficient number, since it is larger than the sum of its proper divisors (343477).

51155723 is a wasteful number, since it uses less digits than its factorization.

51155723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343476.

The product of its digits is 5250, while the sum is 29.

The square root of 51155723 is about 7152.3229093771. The cubic root of 51155723 is about 371.2200364288.

The spelling of 51155723 in words is "fifty-one million, one hundred fifty-five thousand, seven hundred twenty-three".