20842920 has 160 divisors (see below), whose sum is σ = 80150400. Its totient is φ = 4758912.

The previous prime is 20842919. The next prime is 20842933. The reversal of 20842920 is 2924802.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 22221 + ... + 23139.

It is an arithmetic number, because the mean of its divisors is an integer number (500940).

Almost surely, 2^20842920 is an apocalyptic number.

20842920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20842920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40075200).

20842920 is an abundant number, since it is smaller than the sum of its proper divisors (59307480).

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

20842920 is a wasteful number, since it uses less digits than its factorization.

20842920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 949 (or 936 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 20842920 is about 4565.4046918099. The cubic root of 20842920 is about 275.2028035702.

The spelling of 20842920 in words is "twenty million, eight hundred forty-two thousand, nine hundred twenty".