20782215 has 24 divisors (see below), whose sum is σ = 36296208. Its totient is φ = 10999680.

The previous prime is 20782213. The next prime is 20782217. The reversal of 20782215 is 51228702.

It is an interprime number because it is at equal distance from previous prime (20782213) and next prime (20782217).

It is not a de Polignac number, because 20782215 - 2¹ = 20782213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20782213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4480 + ... + 7850.

It is an arithmetic number, because the mean of its divisors is an integer number (1512342).

Almost surely, 2^20782215 is an apocalyptic number.

20782215 is a deficient number, since it is larger than the sum of its proper divisors (15513993).

20782215 is a wasteful number, since it uses less digits than its factorization.

20782215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3519 (or 3516 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 20782215 is about 4558.7514738139. The cubic root of 20782215 is about 274.9353677310.

The spelling of 20782215 in words is "twenty million, seven hundred eighty-two thousand, two hundred fifteen".