51913729 has 4 divisors (see below), whose sum is σ = 59329984. Its totient is φ = 44497476.

The previous prime is 51913723. The next prime is 51913753. The reversal of 51913729 is 92731915.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92731915 = 5 ⋅18546383.

It is a cyclic number.

It is not a de Polignac number, because 51913729 - 2⁷ = 51913601 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51913723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3708117 + ... + 3708130.

It is an arithmetic number, because the mean of its divisors is an integer number (14832496).

Almost surely, 2^51913729 is an apocalyptic number.

It is an amenable number.

51913729 is a deficient number, since it is larger than the sum of its proper divisors (7416255).

51913729 is an equidigital number, since it uses as much as digits as its factorization.

51913729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7416254.

The product of its digits is 17010, while the sum is 37.

The square root of 51913729 is about 7205.1182502441. The cubic root of 51913729 is about 373.0445863800.

The spelling of 51913729 in words is "fifty-one million, nine hundred thirteen thousand, seven hundred twenty-nine".