20021776 has 40 divisors (see below), whose sum is σ = 41497344. Its totient is φ = 9335040.

The previous prime is 20021759. The next prime is 20021821. The reversal of 20021776 is 67712002.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20021776.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14425 + ... + 15751.

Almost surely, 2^20021776 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20021776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20748672).

20021776 is an abundant number, since it is smaller than the sum of its proper divisors (21475568).

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

20021776 is a wasteful number, since it uses less digits than its factorization.

20021776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1399 (or 1393 counting only the distinct ones).

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 20021776 is about 4474.5699234675. The cubic root of 20021776 is about 271.5402411900.

Adding to 20021776 its reverse (67712002), we get a palindrome (87733778).

The spelling of 20021776 in words is "twenty million, twenty-one thousand, seven hundred seventy-six".