20868140 has 24 divisors (see below), whose sum is σ = 44008272. Its totient is φ = 8312000.

The previous prime is 20868131. The next prime is 20868149. The reversal of 20868140 is 4186802.

It is an interprime number because it is at equal distance from previous prime (20868131) and next prime (20868149).

It is not an unprimeable number, because it can be changed into a prime (20868149) 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 7 ways as a sum of consecutive naturals, for example, 2942 + ... + 7098.

It is an arithmetic number, because the mean of its divisors is an integer number (1833678).

Almost surely, 2^20868140 is an apocalyptic number.

20868140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20868140 is an abundant number, since it is smaller than the sum of its proper divisors (23140132).

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

20868140 is a wasteful number, since it uses less digits than its factorization.

20868140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4417 (or 4415 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 20868140 is about 4568.1659339389. The cubic root of 20868140 is about 275.3137575888.

The spelling of 20868140 in words is "twenty million, eight hundred sixty-eight thousand, one hundred forty".