21194043 has 16 divisors (see below), whose sum is σ = 30890496. Its totient is φ = 12846240.

The previous prime is 21194029. The next prime is 21194077. The reversal of 21194043 is 34049112.

It is not a de Polignac number, because 21194043 - 2¹² = 21189947 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21194083) 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 15 ways as a sum of consecutive naturals, for example, 1443 + ... + 6668.

It is an arithmetic number, because the mean of its divisors is an integer number (1930656).

Almost surely, 2^21194043 is an apocalyptic number.

21194043 is a deficient number, since it is larger than the sum of its proper divisors (9696453).

21194043 is a wasteful number, since it uses less digits than its factorization.

21194043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8194.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21194043 is about 4603.6988389772. The cubic root of 21194043 is about 276.7395754689.

The spelling of 21194043 in words is "twenty-one million, one hundred ninety-four thousand, forty-three".