51232221 has 12 divisors (see below), whose sum is σ = 75723648. Its totient is φ = 33360264.

The previous prime is 51232219. The next prime is 51232261. The reversal of 51232221 is 12223215.

It is not a de Polignac number, because 51232221 - 2¹ = 51232219 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 51232194 and 51232203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51232261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65805 + ... + 66578.

It is an arithmetic number, because the mean of its divisors is an integer number (6310304).

Almost surely, 2^51232221 is an apocalyptic number.

It is an amenable number.

51232221 is a deficient number, since it is larger than the sum of its proper divisors (24491427).

51232221 is a wasteful number, since it uses less digits than its factorization.

51232221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132432 (or 132429 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 51232221 is about 7157.6686847045. The cubic root of 51232221 is about 371.4049844348.

Adding to 51232221 its reverse (12223215), we get a palindrome (63455436).

The spelling of 51232221 in words is "fifty-one million, two hundred thirty-two thousand, two hundred twenty-one".