20983280 has 40 divisors (see below), whose sum is σ = 50365824. Its totient is φ = 8121600.

The previous prime is 20983273. The next prime is 20983289. The reversal of 20983280 is 8238902.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20983289) 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, 1751 + ... + 6710.

Almost surely, 2^20983280 is an apocalyptic number.

20983280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20983280 is an abundant number, since it is smaller than the sum of its proper divisors (29382544).

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

20983280 is a wasteful number, since it uses less digits than its factorization.

20983280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8505 (or 8499 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 20983280 is about 4580.7510301260. The cubic root of 20983280 is about 275.8191772251.

The spelling of 20983280 in words is "twenty million, nine hundred eighty-three thousand, two hundred eighty".