51123213 has 6 divisors (see below), whose sum is σ = 73844654. Its totient is φ = 34082136.

The previous prime is 51123197. The next prime is 51123221. The reversal of 51123213 is 31232115.

It can be written as a sum of positive squares in only one way, i.e., 27910089 + 23213124 = 5283^2 + 4818^2 .

It is not a de Polignac number, because 51123213 - 2⁴ = 51123197 is a prime.

It is a super-2 number, since 2×51123213² = 5227165814886738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51123253) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2840170 + ... + 2840187.

Almost surely, 2^51123213 is an apocalyptic number.

It is an amenable number.

51123213 is a deficient number, since it is larger than the sum of its proper divisors (22721441).

51123213 is a wasteful number, since it uses less digits than its factorization.

51123213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5680363 (or 5680360 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 51123213 is about 7150.0498599660. The cubic root of 51123213 is about 371.1413816854.

Adding to 51123213 its reverse (31232115), we get a palindrome (82355328).

The spelling of 51123213 in words is "fifty-one million, one hundred twenty-three thousand, two hundred thirteen".