21965194 has 4 divisors (see below), whose sum is σ = 32947794. Its totient is φ = 10982596.

The previous prime is 21965149. The next prime is 21965219. The reversal of 21965194 is 49156912.

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., 10989225 + 10975969 = 3315^2 + 3313^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5491297 + ... + 5491300.

Almost surely, 2^21965194 is an apocalyptic number.

21965194 is a deficient number, since it is larger than the sum of its proper divisors (10982600).

21965194 is a wasteful number, since it uses less digits than its factorization.

21965194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10982599.

The product of its digits is 19440, while the sum is 37.

The square root of 21965194 is about 4686.7039590740. The cubic root of 21965194 is about 280.0560857037.

The spelling of 21965194 in words is "twenty-one million, nine hundred sixty-five thousand, one hundred ninety-four".