216221346 has 64 divisors (see below), whose sum is σ = 528197760. Its totient is φ = 65018880.

The previous prime is 216221323. The next prime is 216221389. The reversal of 216221346 is 643122612.

216221346 is a `hidden beast` number, since 2 + 1 + 622 + 1 + 34 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 31 ways as a sum of consecutive naturals, for example, 80050 + ... + 82706.

It is an arithmetic number, because the mean of its divisors is an integer number (8253090).

Almost surely, 2^216221346 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216221346, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264098880).

216221346 is an abundant number, since it is smaller than the sum of its proper divisors (311976414).

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

216221346 is a wasteful number, since it uses less digits than its factorization.

216221346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2816 (or 2810 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 216221346 is about 14704.4668723487. The cubic root of 216221346 is about 600.2048800323.

Adding to 216221346 its reverse (643122612), we get a palindrome (859343958).

The spelling of 216221346 in words is "two hundred sixteen million, two hundred twenty-one thousand, three hundred forty-six".