20782505 has 8 divisors (see below), whose sum is σ = 24969600. Its totient is φ = 16605616.

The previous prime is 20782499. The next prime is 20782513. The reversal of 20782505 is 50528702.

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 20782505 - 2¹⁴ = 20766121 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3056 + ... + 7134.

It is an arithmetic number, because the mean of its divisors is an integer number (3121200).

Almost surely, 2^20782505 is an apocalyptic number.

It is an amenable number.

20782505 is a deficient number, since it is larger than the sum of its proper divisors (4187095).

20782505 is a wasteful number, since it uses less digits than its factorization.

20782505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5103.

The product of its (nonzero) digits is 5600, while the sum is 29.

The square root of 20782505 is about 4558.7832806572. The cubic root of 20782505 is about 274.9366465630.

The spelling of 20782505 in words is "twenty million, seven hundred eighty-two thousand, five hundred five".