20287008 has 144 divisors (see below), whose sum is σ = 68402880. Its totient is φ = 5580288.

The previous prime is 20286977. The next prime is 20287039. The reversal of 20287008 is 80078202.

It is an interprime number because it is at equal distance from previous prime (20286977) and next prime (20287039).

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 58291 + ... + 58637.

It is an arithmetic number, because the mean of its divisors is an integer number (475020).

Almost surely, 2^20287008 is an apocalyptic number.

20287008 is a gapful number since it is divisible by the number (28) 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 20287008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34201440).

20287008 is an abundant number, since it is smaller than the sum of its proper divisors (48115872).

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

20287008 is a wasteful number, since it uses less digits than its factorization.

20287008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 20287008 is about 4504.1101229877. The cubic root of 20287008 is about 272.7340323173.

The spelling of 20287008 in words is "twenty million, two hundred eighty-seven thousand, eight".