30720222 has 80 divisors (see below), whose sum is σ = 76839840. Its totient is φ = 9108288.

The previous prime is 30720199. The next prime is 30720247. The reversal of 30720222 is 22202703.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 30720195 and 30720204.

It is a congruent number.

It is an unprimeable number.

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 39 ways as a sum of consecutive naturals, for example, 60823 + ... + 61325.

It is an arithmetic number, because the mean of its divisors is an integer number (960498).

Almost surely, 2^30720222 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30720222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38419920).

30720222 is an abundant number, since it is smaller than the sum of its proper divisors (46119618).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

30720222 is a wasteful number, since it uses less digits than its factorization.

30720222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559 (or 550 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 18.

The square root of 30720222 is about 5542.5826110217. The cubic root of 30720222 is about 313.1901657193.

Adding to 30720222 its reverse (22202703), we get a palindrome (52922925).

The spelling of 30720222 in words is "thirty million, seven hundred twenty thousand, two hundred twenty-two".