21421141 has 4 divisors (see below), whose sum is σ = 24481312. Its totient is φ = 18360972.

The previous prime is 21421133. The next prime is 21421159. The reversal of 21421141 is 14112412.

It is a happy number.

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 not a de Polignac number, because 21421141 - 2³ = 21421133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21421541) 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 3 ways as a sum of consecutive naturals, for example, 1530075 + ... + 1530088.

It is an arithmetic number, because the mean of its divisors is an integer number (6120328).

Almost surely, 2^21421141 is an apocalyptic number.

It is an amenable number.

21421141 is a deficient number, since it is larger than the sum of its proper divisors (3060171).

21421141 is an equidigital number, since it uses as much as digits as its factorization.

21421141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3060170.

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

The square root of 21421141 is about 4628.2978512624. The cubic root of 21421141 is about 277.7245040887.

Adding to 21421141 its reverse (14112412), we get a palindrome (35533553).

The spelling of 21421141 in words is "twenty-one million, four hundred twenty-one thousand, one hundred forty-one".