21461143 has 4 divisors (see below), whose sum is σ = 23412168. Its totient is φ = 19510120.

The previous prime is 21461137. The next prime is 21461173. The reversal of 21461143 is 34116412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21461143 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21461113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 975496 + ... + 975517.

It is an arithmetic number, because the mean of its divisors is an integer number (5853042).

Almost surely, 2^21461143 is an apocalyptic number.

21461143 is a deficient number, since it is larger than the sum of its proper divisors (1951025).

21461143 is a wasteful number, since it uses less digits than its factorization.

21461143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1951024.

The product of its digits is 576, while the sum is 22.

The square root of 21461143 is about 4632.6172947914. The cubic root of 21461143 is about 277.8972715343.

Adding to 21461143 its reverse (34116412), we get a palindrome (55577555).

It can be divided in two parts, 21 and 461143, that added together give a palindrome (461164).

The spelling of 21461143 in words is "twenty-one million, four hundred sixty-one thousand, one hundred forty-three".