21143494 has 8 divisors (see below), whose sum is σ = 32808960. Its totient is φ = 10207176.

The previous prime is 21143491. The next prime is 21143497. The reversal of 21143494 is 49434112.

It is an interprime number because it is at equal distance from previous prime (21143491) and next prime (21143497).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21143491) 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, 182214 + ... + 182329.

It is an arithmetic number, because the mean of its divisors is an integer number (4101120).

Almost surely, 2^21143494 is an apocalyptic number.

21143494 is a deficient number, since it is larger than the sum of its proper divisors (11665466).

21143494 is a wasteful number, since it uses less digits than its factorization.

21143494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364574.

The product of its digits is 3456, while the sum is 28.

The square root of 21143494 is about 4598.2055195478. The cubic root of 21143494 is about 276.5193871042.

The spelling of 21143494 in words is "twenty-one million, one hundred forty-three thousand, four hundred ninety-four".