51222239 has 4 divisors (see below), whose sum is σ = 51293424. Its totient is φ = 51151056.

The previous prime is 51222211. The next prime is 51222247. The reversal of 51222239 is 93222215.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93222215 = 5 ⋅18644443.

It is a cyclic number.

It is not a de Polignac number, because 51222239 - 2²⁰ = 50173663 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51222289) 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, 34502 + ... + 35955.

It is an arithmetic number, because the mean of its divisors is an integer number (12823356).

Almost surely, 2^51222239 is an apocalyptic number.

51222239 is a deficient number, since it is larger than the sum of its proper divisors (71185).

51222239 is an equidigital number, since it uses as much as digits as its factorization.

51222239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71184.

The product of its digits is 2160, while the sum is 26.

The square root of 51222239 is about 7156.9713566564. The cubic root of 51222239 is about 371.3808615600.

The spelling of 51222239 in words is "fifty-one million, two hundred twenty-two thousand, two hundred thirty-nine".