20628280 has 32 divisors (see below), whose sum is σ = 48016800. Its totient is φ = 7966336.

The previous prime is 20628271. The next prime is 20628287. The reversal of 20628280 is 8282602.

It is a happy number.

It is a super-3 number, since 3×20628280³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20628287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7732 + ... + 10051.

It is an arithmetic number, because the mean of its divisors is an integer number (1500525).

Almost surely, 2^20628280 is an apocalyptic number.

20628280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20628280 is an abundant number, since it is smaller than the sum of its proper divisors (27388520).

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

20628280 is a wasteful number, since it uses less digits than its factorization.

20628280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17823 (or 17819 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 20628280 is about 4541.8366329052. The cubic root of 20628280 is about 274.2548643585.

The spelling of 20628280 in words is "twenty million, six hundred twenty-eight thousand, two hundred eighty".