16101221 has 4 divisors (see below), whose sum is σ = 16475712. Its totient is φ = 15726732.

The previous prime is 16101209. The next prime is 16101223. The reversal of 16101221 is 12210161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16101221 - 2⁶ = 16101157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16101196 and 16101205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16101223) 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, 187181 + ... + 187266.

It is an arithmetic number, because the mean of its divisors is an integer number (4118928).

Almost surely, 2^16101221 is an apocalyptic number.

It is an amenable number.

16101221 is a deficient number, since it is larger than the sum of its proper divisors (374491).

16101221 is an equidigital number, since it uses as much as digits as its factorization.

16101221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374490.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 16101221 is about 4012.6326769342. The cubic root of 16101221 is about 252.5144703010.

Adding to 16101221 its reverse (12210161), we get a palindrome (28311382).

The spelling of 16101221 in words is "sixteen million, one hundred one thousand, two hundred twenty-one".