16221580 has 24 divisors (see below), whose sum is σ = 34792128. Its totient is φ = 6350208.

The previous prime is 16221563. The next prime is 16221581. The reversal of 16221580 is 8512261.

It is not an unprimeable number, because it can be changed into a prime (16221581) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 7689 + ... + 9568.

It is an arithmetic number, because the mean of its divisors is an integer number (1449672).

Almost surely, 2^16221580 is an apocalyptic number.

16221580 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16221580 is an abundant number, since it is smaller than the sum of its proper divisors (18570548).

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

16221580 is a wasteful number, since it uses less digits than its factorization.

16221580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17313 (or 17311 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 16221580 is about 4027.6022643752. The cubic root of 16221580 is about 253.1421032999.

The spelling of 16221580 in words is "sixteen million, two hundred twenty-one thousand, five hundred eighty".