21191194 has 8 divisors (see below), whose sum is σ = 33459840. Its totient is φ = 10037916.

The previous prime is 21191173. The next prime is 21191201. The reversal of 21191194 is 49119112.

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 278794 + ... + 278869.

It is an arithmetic number, because the mean of its divisors is an integer number (4182480).

Almost surely, 2^21191194 is an apocalyptic number.

21191194 is a deficient number, since it is larger than the sum of its proper divisors (12268646).

21191194 is a wasteful number, since it uses less digits than its factorization.

21191194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557684.

The product of its digits is 648, while the sum is 28.

The square root of 21191194 is about 4603.3894034722. The cubic root of 21191194 is about 276.7271747143.

It can be divided in two parts, 2 and 1191194, that added together give a triangular number (1191196 = T₁₅₄₃).

The spelling of 21191194 in words is "twenty-one million, one hundred ninety-one thousand, one hundred ninety-four".