51501213 has 24 divisors (see below), whose sum is σ = 76616280. Its totient is φ = 33321600.

The previous prime is 51501179. The next prime is 51501221. The reversal of 51501213 is 31210515.

51501213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 25674489 + 25826724 = 5067^2 + 5082^2 .

It is not a de Polignac number, because 51501213 - 2¹⁶ = 51435677 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51501223) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 47643 + ... + 48711.

It is an arithmetic number, because the mean of its divisors is an integer number (3192345).

Almost surely, 2^51501213 is an apocalyptic number.

51501213 is a gapful number since it is divisible by the number (53) formed by its first and last digit.

It is an amenable number.

51501213 is a deficient number, since it is larger than the sum of its proper divisors (25115067).

51501213 is a wasteful number, since it uses less digits than its factorization.

51501213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1229 (or 1226 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 51501213 is about 7176.4345604207. The cubic root of 51501213 is about 372.0538640352.

Adding to 51501213 its reverse (31210515), we get a palindrome (82711728).

It can be divided in two parts, 51 and 501213, that added together give a square (501264 = 708²).

The spelling of 51501213 in words is "fifty-one million, five hundred one thousand, two hundred thirteen".