51724691 has 4 divisors (see below), whose sum is σ = 51818112. Its totient is φ = 51631272.

The previous prime is 51724681. The next prime is 51724703. The reversal of 51724691 is 19642715.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51724691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51724601) 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, 45875 + ... + 46988.

It is an arithmetic number, because the mean of its divisors is an integer number (12954528).

Almost surely, 2^51724691 is an apocalyptic number.

51724691 is a deficient number, since it is larger than the sum of its proper divisors (93421).

51724691 is an equidigital number, since it uses as much as digits as its factorization.

51724691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93420.

The product of its digits is 15120, while the sum is 35.

The square root of 51724691 is about 7191.9879727374. The cubic root of 51724691 is about 372.5912357034.

The spelling of 51724691 in words is "fifty-one million, seven hundred twenty-four thousand, six hundred ninety-one".