20782985 has 8 divisors (see below), whose sum is σ = 25050816. Its totient is φ = 16552240.

The previous prime is 20782981. The next prime is 20782987. The reversal of 20782985 is 58928702.

It is a happy number.

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

It is not a de Polignac number, because 20782985 - 2² = 20782981 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20782981) 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, 8021 + ... + 10290.

It is an arithmetic number, because the mean of its divisors is an integer number (3131352).

Almost surely, 2^20782985 is an apocalyptic number.

It is an amenable number.

20782985 is a deficient number, since it is larger than the sum of its proper divisors (4267831).

20782985 is a wasteful number, since it uses less digits than its factorization.

20782985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18543.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 20782985 is about 4558.8359259794. The cubic root of 20782985 is about 274.9387632244.

The spelling of 20782985 in words is "twenty million, seven hundred eighty-two thousand, nine hundred eighty-five".