20280140 has 12 divisors (see below), whose sum is σ = 42588336. Its totient is φ = 8112048.

The previous prime is 20280119. The next prime is 20280149. The reversal of 20280140 is 4108202.

It is a super-2 number, since 2×20280140² = 822568156839200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20280149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 506984 + ... + 507023.

It is an arithmetic number, because the mean of its divisors is an integer number (3549028).

Almost surely, 2^20280140 is an apocalyptic number.

20280140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20280140 is an abundant number, since it is smaller than the sum of its proper divisors (22308196).

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

20280140 is a wasteful number, since it uses less digits than its factorization.

20280140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1014016 (or 1014014 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 20280140 is about 4503.3476436980. The cubic root of 20280140 is about 272.7032515544.

Adding to 20280140 its reverse (4108202), we get a palindrome (24388342).

The spelling of 20280140 in words is "twenty million, two hundred eighty thousand, one hundred forty".