51523729 has 4 divisors (see below), whose sum is σ = 51562420. Its totient is φ = 51485040.

The previous prime is 51523727. The next prime is 51523783. The reversal of 51523729 is 92732515.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92732515 = 5 ⋅18546503.

It can be written as a sum of positive squares in 2 ways, for example, as 24275329 + 27248400 = 4927^2 + 5220^2 .

It is a cyclic number.

It is not a de Polignac number, because 51523729 - 2¹ = 51523727 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51523694 and 51523703.

It is not an unprimeable number, because it can be changed into a prime (51523727) 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, 17274 + ... + 20035.

It is an arithmetic number, because the mean of its divisors is an integer number (12890605).

Almost surely, 2^51523729 is an apocalyptic number.

It is an amenable number.

51523729 is a deficient number, since it is larger than the sum of its proper divisors (38691).

51523729 is a wasteful number, since it uses less digits than its factorization.

51523729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38690.

The product of its digits is 18900, while the sum is 34.

The square root of 51523729 is about 7178.0031345772. The cubic root of 51523729 is about 372.1080759900.

The spelling of 51523729 in words is "fifty-one million, five hundred twenty-three thousand, seven hundred twenty-nine".