16221961 has 8 divisors (see below), whose sum is σ = 19630080. Its totient is φ = 13086528.

The previous prime is 16221929. The next prime is 16221971. The reversal of 16221961 is 16912261.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 16221961 - 2⁵ = 16221929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16221901) 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, 68041 + ... + 68278.

It is an arithmetic number, because the mean of its divisors is an integer number (2453760).

Almost surely, 2^16221961 is an apocalyptic number.

It is an amenable number.

16221961 is a deficient number, since it is larger than the sum of its proper divisors (3408119).

16221961 is a wasteful number, since it uses less digits than its factorization.

16221961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136343.

The product of its digits is 1296, while the sum is 28.

The square root of 16221961 is about 4027.6495627102. The cubic root of 16221961 is about 253.1440851535.

The spelling of 16221961 in words is "sixteen million, two hundred twenty-one thousand, nine hundred sixty-one".