216422720 has 56 divisors (see below), whose sum is σ = 517269984. Its totient is φ = 86247936.

The previous prime is 216422719. The next prime is 216422729. The reversal of 216422720 is 27224612.

It is a self number, because there is not a number n which added to its sum of digits gives 216422720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216422729) 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, 97139 + ... + 99341.

It is an arithmetic number, because the mean of its divisors is an integer number (9236964).

Almost surely, 2^216422720 is an apocalyptic number.

216422720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216422720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258634992).

216422720 is an abundant number, since it is smaller than the sum of its proper divisors (300847264).

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

216422720 is a wasteful number, since it uses less digits than its factorization.

216422720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2527 (or 2517 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 216422720 is about 14711.3126538729. The cubic root of 216422720 is about 600.3911523517.

The spelling of 216422720 in words is "two hundred sixteen million, four hundred twenty-two thousand, seven hundred twenty".