20844890 has 64 divisors (see below), whose sum is σ = 44229888. Its totient is φ = 6988800.

The previous prime is 20844883. The next prime is 20844937. The reversal of 20844890 is 9844802.

It is a super-2 number, since 2×20844890² = 869018878224200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20844890.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 132692 + ... + 132848.

It is an arithmetic number, because the mean of its divisors is an integer number (691092).

Almost surely, 2^20844890 is an apocalyptic number.

20844890 is an abundant number, since it is smaller than the sum of its proper divisors (23384998).

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

20844890 is a wasteful number, since it uses less digits than its factorization.

20844890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263.

The product of its (nonzero) digits is 18432, while the sum is 35.

The square root of 20844890 is about 4565.6204397650. The cubic root of 20844890 is about 275.2114736997.

The spelling of 20844890 in words is "twenty million, eight hundred forty-four thousand, eight hundred ninety".