20428776 has 48 divisors (see below), whose sum is σ = 55692000. Its totient is φ = 6764832.

The previous prime is 20428757. The next prime is 20428777. The reversal of 20428776 is 67782402.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20428776.

It is not an unprimeable number, because it can be changed into a prime (20428777) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11175 + ... + 12873.

It is an arithmetic number, because the mean of its divisors is an integer number (1160250).

Almost surely, 2^20428776 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 20428776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27846000).

20428776 is an abundant number, since it is smaller than the sum of its proper divisors (35263224).

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

20428776 is a wasteful number, since it uses less digits than its factorization.

20428776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1878 (or 1871 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 20428776 is about 4519.8203504122. The cubic root of 20428776 is about 273.3678573617.

The spelling of 20428776 in words is "twenty million, four hundred twenty-eight thousand, seven hundred seventy-six".