21894986 has 8 divisors (see below), whose sum is σ = 32965380. Its totient is φ = 10906528.

The previous prime is 21894967. The next prime is 21894991. The reversal of 21894986 is 68949812.

It can be written as a sum of positive squares in 2 ways, for example, as 14707225 + 7187761 = 3835^2 + 2681^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 21894986.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19811 + ... + 20886.

Almost surely, 2^21894986 is an apocalyptic number.

21894986 is a deficient number, since it is larger than the sum of its proper divisors (11070394).

21894986 is a wasteful number, since it uses less digits than its factorization.

21894986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40968.

The product of its digits is 248832, while the sum is 47.

The square root of 21894986 is about 4679.2078389403. The cubic root of 21894986 is about 279.7573833738.

The spelling of 21894986 in words is "twenty-one million, eight hundred ninety-four thousand, nine hundred eighty-six".