16211421 has 40 divisors (see below), whose sum is σ = 26196984. Its totient is φ = 9953280.

The previous prime is 16211417. The next prime is 16211449. The reversal of 16211421 is 12411261.

16211421 is a `hidden beast` number, since 1 + 621 + 1 + 42 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 171396 + 16040025 = 414^2 + 4005^2 .

It is not a de Polignac number, because 16211421 - 2² = 16211417 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 16211394 and 16211403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16211401) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 83901 + ... + 84093.

Almost surely, 2^16211421 is an apocalyptic number.

It is an amenable number.

16211421 is a deficient number, since it is larger than the sum of its proper divisors (9985563).

16211421 is a wasteful number, since it uses less digits than its factorization.

16211421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283 (or 274 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 16211421 is about 4026.3408946586. The cubic root of 16211421 is about 253.0892476253.

Adding to 16211421 its reverse (12411261), we get a palindrome (28622682).

The spelling of 16211421 in words is "sixteen million, two hundred eleven thousand, four hundred twenty-one".