51709331 has 4 divisors (see below), whose sum is σ = 52417752. Its totient is φ = 51000912.

The previous prime is 51709309. The next prime is 51709367. The reversal of 51709331 is 13390715.

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-51709331 is a prime.

It is a super-2 number, since 2×51709331² = 5347709824935122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51709294 and 51709303.

It is not an unprimeable number, because it can be changed into a prime (51709531) 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, 354101 + ... + 354246.

It is an arithmetic number, because the mean of its divisors is an integer number (13104438).

Almost surely, 2^51709331 is an apocalyptic number.

51709331 is a deficient number, since it is larger than the sum of its proper divisors (708421).

51709331 is an equidigital number, since it uses as much as digits as its factorization.

51709331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708420.

The product of its (nonzero) digits is 2835, while the sum is 29.

The square root of 51709331 is about 7190.9200384930. The cubic root of 51709331 is about 372.5543508820.

The spelling of 51709331 in words is "fifty-one million, seven hundred nine thousand, three hundred thirty-one".