16221012 has 12 divisors (see below), whose sum is σ = 37849056. Its totient is φ = 5407000.

The previous prime is 16220977. The next prime is 16221017. The reversal of 16221012 is 21012261.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 16220982 and 16221000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221017) 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 3 ways as a sum of consecutive naturals, for example, 675864 + ... + 675887.

It is an arithmetic number, because the mean of its divisors is an integer number (3154088).

Almost surely, 2^16221012 is an apocalyptic number.

16221012 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

16221012 is an abundant number, since it is smaller than the sum of its proper divisors (21628044).

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

16221012 is a wasteful number, since it uses less digits than its factorization.

16221012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1351758 (or 1351756 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 16221012 is about 4027.5317503404. The cubic root of 16221012 is about 253.1391486681.

Adding to 16221012 its reverse (21012261), we get a palindrome (37233273).

The spelling of 16221012 in words is "sixteen million, two hundred twenty-one thousand, twelve".