20855580 has 48 divisors (see below), whose sum is σ = 58730784. Its totient is φ = 5529600.

The previous prime is 20855563. The next prime is 20855581. The reversal of 20855580 is 8555802.

It is a super-3 number, since 3×20855580³ (a number of 23 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20855581) 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, 10680 + ... + 12480.

It is an arithmetic number, because the mean of its divisors is an integer number (1223558).

Almost surely, 2^20855580 is an apocalyptic number.

20855580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20855580 is an abundant number, since it is smaller than the sum of its proper divisors (37875204).

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

20855580 is a wasteful number, since it uses less digits than its factorization.

20855580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2006 (or 2004 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 33.

The square root of 20855580 is about 4566.7909958745. The cubic root of 20855580 is about 275.2585117327.

The spelling of 20855580 in words is "twenty million, eight hundred fifty-five thousand, five hundred eighty".