21141421 has 16 divisors (see below), whose sum is σ = 25850880. Its totient is φ = 16876800.

The previous prime is 21141403. The next prime is 21141431. The reversal of 21141421 is 12414112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21141421 - 2⁵ = 21141389 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21141395 and 21141404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21141431) 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 15 ways as a sum of consecutive naturals, for example, 11140 + ... + 12898.

It is an arithmetic number, because the mean of its divisors is an integer number (1615680).

Almost surely, 2^21141421 is an apocalyptic number.

It is an amenable number.

21141421 is a deficient number, since it is larger than the sum of its proper divisors (4709459).

21141421 is a wasteful number, since it uses less digits than its factorization.

21141421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1884.

The product of its digits is 64, while the sum is 16.

The square root of 21141421 is about 4597.9801000004. The cubic root of 21141421 is about 276.5103497549.

Adding to 21141421 its reverse (12414112), we get a palindrome (33555533).

The spelling of 21141421 in words is "twenty-one million, one hundred forty-one thousand, four hundred twenty-one".