21194331 has 8 divisors (see below), whose sum is σ = 29233680. Its totient is φ = 13642272.

The previous prime is 21194323. The next prime is 21194333. The reversal of 21194331 is 13349112.

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

It is not a de Polignac number, because 21194331 - 2³ = 21194323 is a prime.

It is a super-2 number, since 2×21194331² = 898399333075122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21194333) 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 7 ways as a sum of consecutive naturals, for example, 121720 + ... + 121893.

It is an arithmetic number, because the mean of its divisors is an integer number (3654210).

Almost surely, 2^21194331 is an apocalyptic number.

21194331 is a deficient number, since it is larger than the sum of its proper divisors (8039349).

21194331 is a wasteful number, since it uses less digits than its factorization.

21194331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243645.

The product of its digits is 648, while the sum is 24.

The square root of 21194331 is about 4603.7301180673. The cubic root of 21194331 is about 276.7408289758.

The spelling of 21194331 in words is "twenty-one million, one hundred ninety-four thousand, three hundred thirty-one".