51561212 has 12 divisors (see below), whose sum is σ = 94981320. Its totient is φ = 24423696.

The previous prime is 51561203. The next prime is 51561233. The reversal of 51561212 is 21216515.

It is a happy number.

51561212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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, 339143 + ... + 339294.

It is an arithmetic number, because the mean of its divisors is an integer number (7915110).

Almost surely, 2^51561212 is an apocalyptic number.

It is an amenable number.

51561212 is a deficient number, since it is larger than the sum of its proper divisors (43420108).

51561212 is a wasteful number, since it uses less digits than its factorization.

51561212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678460 (or 678458 counting only the distinct ones).

The product of its digits is 600, while the sum is 23.

The square root of 51561212 is about 7180.6136228041. The cubic root of 51561212 is about 372.1982890910.

Adding to 51561212 its reverse (21216515), we get a palindrome (72777727).

The spelling of 51561212 in words is "fifty-one million, five hundred sixty-one thousand, two hundred twelve".