21970245 has 16 divisors (see below), whose sum is σ = 38348352. Its totient is φ = 10652160.

The previous prime is 21970229. The next prime is 21970271. The reversal of 21970245 is 54207912.

It is not a de Polignac number, because 21970245 - 2⁴ = 21970229 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66412 + ... + 66741.

It is an arithmetic number, because the mean of its divisors is an integer number (2396772).

Almost surely, 2^21970245 is an apocalyptic number.

It is an amenable number.

21970245 is a deficient number, since it is larger than the sum of its proper divisors (16378107).

21970245 is a wasteful number, since it uses less digits than its factorization.

21970245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133172.

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 21970245 is about 4687.2427929434. The cubic root of 21970245 is about 280.0775507979.

The spelling of 21970245 in words is "twenty-one million, nine hundred seventy thousand, two hundred forty-five".