21972835 has 8 divisors (see below), whose sum is σ = 27755280. Its totient is φ = 16653024.

The previous prime is 21972833. The next prime is 21972869. The reversal of 21972835 is 53827912.

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

It is a cyclic number.

It is not a de Polignac number, because 21972835 - 2¹ = 21972833 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21972794 and 21972803.

It is not an unprimeable number, because it can be changed into a prime (21972833) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115552 + ... + 115741.

It is an arithmetic number, because the mean of its divisors is an integer number (3469410).

Almost surely, 2^21972835 is an apocalyptic number.

21972835 is a deficient number, since it is larger than the sum of its proper divisors (5782445).

21972835 is a wasteful number, since it uses less digits than its factorization.

21972835 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231317.

The product of its digits is 30240, while the sum is 37.

The square root of 21972835 is about 4687.5190666279. The cubic root of 21972835 is about 280.0885561729.

The spelling of 21972835 in words is "twenty-one million, nine hundred seventy-two thousand, eight hundred thirty-five".