21970786 has 8 divisors (see below), whose sum is σ = 33011280. Its totient is φ = 10967028.

The previous prime is 21970771. The next prime is 21970811. The reversal of 21970786 is 68707912.

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

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, 7636 + ... + 10111.

It is an arithmetic number, because the mean of its divisors is an integer number (4126410).

Almost surely, 2^21970786 is an apocalyptic number.

21970786 is a deficient number, since it is larger than the sum of its proper divisors (11040494).

21970786 is a wasteful number, since it uses less digits than its factorization.

21970786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18368.

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 21970786 is about 4687.3005024214. The cubic root of 21970786 is about 280.0798496755.

The spelling of 21970786 in words is "twenty-one million, nine hundred seventy thousand, seven hundred eighty-six".