51223013 has 4 divisors (see below), whose sum is σ = 51676428. Its totient is φ = 50769600.

The previous prime is 51223009. The next prime is 51223027. The reversal of 51223013 is 31032215.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9012004 + 42211009 = 3002^2 + 6497^2 .

It is a cyclic number.

It is not a de Polignac number, because 51223013 - 2² = 51223009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 51222982 and 51223000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51223043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226538 + ... + 226763.

It is an arithmetic number, because the mean of its divisors is an integer number (12919107).

Almost surely, 2^51223013 is an apocalyptic number.

It is an amenable number.

51223013 is a deficient number, since it is larger than the sum of its proper divisors (453415).

51223013 is a wasteful number, since it uses less digits than its factorization.

51223013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453414.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 51223013 is about 7157.0254296041. The cubic root of 51223013 is about 371.3827321495.

Adding to 51223013 its reverse (31032215), we get a palindrome (82255228).

The spelling of 51223013 in words is "fifty-one million, two hundred twenty-three thousand, thirteen".