21145411 has 12 divisors (see below), whose sum is σ = 24682368. Its totient is φ = 18062352.

The previous prime is 21145409. The next prime is 21145417. The reversal of 21145411 is 11454112.

It is not a de Polignac number, because 21145411 - 2¹ = 21145409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21145417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18910 + ... + 19996.

It is an arithmetic number, because the mean of its divisors is an integer number (2056864).

Almost surely, 2^21145411 is an apocalyptic number.

21145411 is a deficient number, since it is larger than the sum of its proper divisors (3536957).

21145411 is a wasteful number, since it uses less digits than its factorization.

21145411 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1498 (or 1491 counting only the distinct ones).

The product of its digits is 160, while the sum is 19.

The square root of 21145411 is about 4598.4139657060. The cubic root of 21145411 is about 276.5277438379.

Adding to 21145411 its reverse (11454112), we get a palindrome (32599523).

The spelling of 21145411 in words is "twenty-one million, one hundred forty-five thousand, four hundred eleven".