51009913 has 4 divisors (see below), whose sum is σ = 51024208. Its totient is φ = 50995620.

The previous prime is 51009887. The next prime is 51009941. The reversal of 51009913 is 31990015.

51009913 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51009913 is a prime.

It is a super-2 number, since 2×51009913² = 5204022448535138, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51009953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3178 + ... + 10588.

It is an arithmetic number, because the mean of its divisors is an integer number (12756052).

Almost surely, 2^51009913 is an apocalyptic number.

It is an amenable number.

51009913 is a deficient number, since it is larger than the sum of its proper divisors (14295).

51009913 is an equidigital number, since it uses as much as digits as its factorization.

51009913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14294.

The product of its (nonzero) digits is 1215, while the sum is 28.

The square root of 51009913 is about 7142.1224436438. The cubic root of 51009913 is about 370.8670026016.

Adding to 51009913 its reverse (31990015), we get a palindrome (82999928).

The spelling of 51009913 in words is "fifty-one million, nine thousand, nine hundred thirteen".