16221701 has 4 divisors (see below), whose sum is σ = 16781100. Its totient is φ = 15662304.

The previous prime is 16221697. The next prime is 16221703. The reversal of 16221701 is 10712261.

16221701 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5885476 + 10336225 = 2426^2 + 3215^2 .

It is a cyclic number.

It is not a de Polignac number, because 16221701 - 2² = 16221697 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279656 + ... + 279713.

It is an arithmetic number, because the mean of its divisors is an integer number (4195275).

Almost surely, 2^16221701 is an apocalyptic number.

It is an amenable number.

16221701 is a deficient number, since it is larger than the sum of its proper divisors (559399).

16221701 is an equidigital number, since it uses as much as digits as its factorization.

16221701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559398.

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 16221701 is about 4027.6172856914. The cubic root of 16221701 is about 253.1427327109.

Adding to 16221701 its reverse (10712261), we get a palindrome (26933962).

The spelling of 16221701 in words is "sixteen million, two hundred twenty-one thousand, seven hundred one".