16221395 has 8 divisors (see below), whose sum is σ = 19487520. Its totient is φ = 12962560.

The previous prime is 16221391. The next prime is 16221431. The reversal of 16221395 is 59312261.

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

It is not a de Polignac number, because 16221395 - 2² = 16221391 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16221391) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6755 + ... + 8835.

It is an arithmetic number, because the mean of its divisors is an integer number (2435940).

Almost surely, 2^16221395 is an apocalyptic number.

16221395 is a deficient number, since it is larger than the sum of its proper divisors (3266125).

16221395 is a wasteful number, since it uses less digits than its factorization.

16221395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3645.

The product of its digits is 3240, while the sum is 29.

The square root of 16221395 is about 4027.5792977917. The cubic root of 16221395 is about 253.1411409714.

The spelling of 16221395 in words is "sixteen million, two hundred twenty-one thousand, three hundred ninety-five".