20863780 has 24 divisors (see below), whose sum is σ = 50073408. Its totient is φ = 7153248.

The previous prime is 20863763. The next prime is 20863781. The reversal of 20863780 is 8736802.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20863781) 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, 74374 + ... + 74653.

It is an arithmetic number, because the mean of its divisors is an integer number (2086392).

Almost surely, 2^20863780 is an apocalyptic number.

20863780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20863780 is an abundant number, since it is smaller than the sum of its proper divisors (29209628).

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

20863780 is a wasteful number, since it uses less digits than its factorization.

20863780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149043 (or 149041 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 20863780 is about 4567.6886934203. The cubic root of 20863780 is about 275.2945823997.

The spelling of 20863780 in words is "twenty million, eight hundred sixty-three thousand, seven hundred eighty".