20982511 has 4 divisors (see below), whose sum is σ = 22890024. Its totient is φ = 19075000.

The previous prime is 20982503. The next prime is 20982553. The reversal of 20982511 is 11528902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20982511 - 2³ = 20982503 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20982511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20982211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 953740 + ... + 953761.

It is an arithmetic number, because the mean of its divisors is an integer number (5722506).

Almost surely, 2^20982511 is an apocalyptic number.

20982511 is a deficient number, since it is larger than the sum of its proper divisors (1907513).

20982511 is a wasteful number, since it uses less digits than its factorization.

20982511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1907512.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 20982511 is about 4580.6670911560. The cubic root of 20982511 is about 275.8158077560.

The spelling of 20982511 in words is "twenty million, nine hundred eighty-two thousand, five hundred eleven".