51216211 has 4 divisors (see below), whose sum is σ = 51237432. Its totient is φ = 51194992.

The previous prime is 51216203. The next prime is 51216227. The reversal of 51216211 is 11261215.

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

It is a cyclic number.

It is not a de Polignac number, because 51216211 - 2³ = 51216203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51216611) 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, 6445 + ... + 11998.

It is an arithmetic number, because the mean of its divisors is an integer number (12809358).

Almost surely, 2^51216211 is an apocalyptic number.

51216211 is a deficient number, since it is larger than the sum of its proper divisors (21221).

51216211 is a wasteful number, since it uses less digits than its factorization.

51216211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21220.

The product of its digits is 120, while the sum is 19.

The square root of 51216211 is about 7156.5502164101. The cubic root of 51216211 is about 371.3662925518.

Adding to 51216211 its reverse (11261215), we get a palindrome (62477426).

The spelling of 51216211 in words is "fifty-one million, two hundred sixteen thousand, two hundred eleven".