21481411 has 8 divisors (see below), whose sum is σ = 24713984. Its totient is φ = 18289800.

The previous prime is 21481409. The next prime is 21481459. The reversal of 21481411 is 11418412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21481411 - 2¹ = 21481409 is a prime.

It is a super-2 number, since 2×21481411² = 922902037101842, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21481111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9105 + ... + 11218.

It is an arithmetic number, because the mean of its divisors is an integer number (3089248).

Almost surely, 2^21481411 is an apocalyptic number.

21481411 is a deficient number, since it is larger than the sum of its proper divisors (3232573).

21481411 is a wasteful number, since it uses less digits than its factorization.

21481411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20481.

The product of its digits is 256, while the sum is 22.

The square root of 21481411 is about 4634.8043108636. The cubic root of 21481411 is about 277.9847264869.

Adding to 21481411 its reverse (11418412), we get a palindrome (32899823).

The spelling of 21481411 in words is "twenty-one million, four hundred eighty-one thousand, four hundred eleven".