20985582 has 32 divisors (see below), whose sum is σ = 44658432. Its totient is φ = 6551424.

The previous prime is 20985551. The next prime is 20985583. The reversal of 20985582 is 28558902.

It is a self number, because there is not a number n which added to its sum of digits gives 20985582.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20985583) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28503 + ... + 29229.

It is an arithmetic number, because the mean of its divisors is an integer number (1395576).

Almost surely, 2^20985582 is an apocalyptic number.

20985582 is an abundant number, since it is smaller than the sum of its proper divisors (23672850).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20985582 is a wasteful number, since it uses less digits than its factorization.

20985582 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1032.

The product of its (nonzero) digits is 57600, while the sum is 39.

The square root of 20985582 is about 4581.0022920754. The cubic root of 20985582 is about 275.8292632321.

The spelling of 20985582 in words is "twenty million, nine hundred eighty-five thousand, five hundred eighty-two".