21647914 has 8 divisors (see below), whose sum is σ = 32491620. Its totient is φ = 10817376.

The previous prime is 21647911. The next prime is 21647917. The reversal of 21647914 is 41974612.

It is an interprime number because it is at equal distance from previous prime (21647911) and next prime (21647917).

It can be written as a sum of positive squares in 2 ways, for example, as 18774889 + 2873025 = 4333^2 + 1695^2 .

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 21647914.

It is not an unprimeable number, because it can be changed into a prime (21647911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4732 + ... + 8104.

Almost surely, 2^21647914 is an apocalyptic number.

21647914 is a deficient number, since it is larger than the sum of its proper divisors (10843706).

21647914 is a wasteful number, since it uses less digits than its factorization.

21647914 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6584.

The product of its digits is 12096, while the sum is 34.

The square root of 21647914 is about 4652.7318856775. The cubic root of 21647914 is about 278.7011011707.

The spelling of 21647914 in words is "twenty-one million, six hundred forty-seven thousand, nine hundred fourteen".