16221740 has 24 divisors (see below), whose sum is σ = 36070272. Its totient is φ = 6106880.

The previous prime is 16221727. The next prime is 16221743. The reversal of 16221740 is 4712261.

It is not an unprimeable number, because it can be changed into a prime (16221743) 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, 23516 + ... + 24195.

It is an arithmetic number, because the mean of its divisors is an integer number (1502928).

Almost surely, 2^16221740 is an apocalyptic number.

16221740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16221740 is an abundant number, since it is smaller than the sum of its proper divisors (19848532).

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

16221740 is a wasteful number, since it uses less digits than its factorization.

16221740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47737 (or 47735 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 16221740 is about 4027.6221272607. The cubic root of 16221740 is about 253.1429355782.

It can be divided in two parts, 16221 and 740, that added together give a palindrome (16961).

The spelling of 16221740 in words is "sixteen million, two hundred twenty-one thousand, seven hundred forty".