51213223 has 16 divisors (see below), whose sum is σ = 54153792. Its totient is φ = 48384000.

The previous prime is 51213199. The next prime is 51213233. The reversal of 51213223 is 32231215.

It is a cyclic number.

It is not a de Polignac number, because 51213223 - 2⁵ = 51213191 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51213223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51213233) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212383 + ... + 212623.

It is an arithmetic number, because the mean of its divisors is an integer number (3384612).

Almost surely, 2^51213223 is an apocalyptic number.

51213223 is a deficient number, since it is larger than the sum of its proper divisors (2940569).

51213223 is a wasteful number, since it uses less digits than its factorization.

51213223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426.

The product of its digits is 360, while the sum is 19.

The square root of 51213223 is about 7156.3414535641. The cubic root of 51213223 is about 371.3590704631.

Adding to 51213223 its reverse (32231215), we get a palindrome (83444438).

The spelling of 51213223 in words is "fifty-one million, two hundred thirteen thousand, two hundred twenty-three".