20285280 has 72 divisors (see below), whose sum is σ = 69228432. Its totient is φ = 5409024.

The previous prime is 20285263. The next prime is 20285281. The reversal of 20285280 is 8258202.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×20285280² = 822985169356800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20285281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5604 + ... + 8483.

It is an arithmetic number, because the mean of its divisors is an integer number (961506).

Almost surely, 2^20285280 is an apocalyptic number.

20285280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20285280 is an abundant number, since it is smaller than the sum of its proper divisors (48943152).

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

20285280 is a wasteful number, since it uses less digits than its factorization.

20285280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14108 (or 14097 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 27.

The square root of 20285280 is about 4503.9182941079. The cubic root of 20285280 is about 272.7262884813.

The spelling of 20285280 in words is "twenty million, two hundred eighty-five thousand, two hundred eighty".