51253221 has 8 divisors (see below), whose sum is σ = 68372640. Its totient is φ = 34151312.

The previous prime is 51253219. The next prime is 51253271. The reversal of 51253221 is 12235215.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 51253221 - 2¹ = 51253219 is a prime.

It is a super-3 number, since 3×51253221³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51253201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5911 + ... + 11723.

It is an arithmetic number, because the mean of its divisors is an integer number (8546580).

Almost surely, 2^51253221 is an apocalyptic number.

It is an amenable number.

51253221 is a deficient number, since it is larger than the sum of its proper divisors (17119419).

51253221 is a wasteful number, since it uses less digits than its factorization.

51253221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8755.

The product of its digits is 600, while the sum is 21.

The square root of 51253221 is about 7159.1354925019. The cubic root of 51253221 is about 371.4557235927.

Adding to 51253221 its reverse (12235215), we get a palindrome (63488436).

The spelling of 51253221 in words is "fifty-one million, two hundred fifty-three thousand, two hundred twenty-one".