72222720 has 96 divisors (see below), whose sum is σ = 231154560. Its totient is φ = 19251200.

The previous prime is 72222713. The next prime is 72222721. The reversal of 72222720 is 2722227.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×72222720² = 10432242568396800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72222721) 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, 29545 + ... + 31895.

It is an arithmetic number, because the mean of its divisors is an integer number (2407860).

Almost surely, 2^72222720 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72222720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115577280).

72222720 is an abundant number, since it is smaller than the sum of its proper divisors (158931840).

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

72222720 is a wasteful number, since it uses less digits than its factorization.

72222720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2381 (or 2361 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 24.

The square root of 72222720 is about 8498.3951426137. The cubic root of 72222720 is about 416.4452825724.

Adding to 72222720 its reverse (2722227), we get a palindrome (74944947).

The spelling of 72222720 in words is "seventy-two million, two hundred twenty-two thousand, seven hundred twenty".