21365194 has 4 divisors (see below), whose sum is σ = 32047794. Its totient is φ = 10682596.

The previous prime is 21365191. The next prime is 21365203. The reversal of 21365194 is 49156312.

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

It can be written as a sum of positive squares in only one way, i.e., 19474569 + 1890625 = 4413^2 + 1375^2 .

It is not an unprimeable number, because it can be changed into a prime (21365191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5341297 + ... + 5341300.

Almost surely, 2^21365194 is an apocalyptic number.

21365194 is a deficient number, since it is larger than the sum of its proper divisors (10682600).

21365194 is a wasteful number, since it uses less digits than its factorization.

21365194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10682599.

The product of its digits is 6480, while the sum is 31.

The square root of 21365194 is about 4622.2498850668. The cubic root of 21365194 is about 277.4825095163.

The spelling of 21365194 in words is "twenty-one million, three hundred sixty-five thousand, one hundred ninety-four".