20963855 has 12 divisors (see below), whose sum is σ = 27652296. Its totient is φ = 15246000.

The previous prime is 20963851. The next prime is 20963869. The reversal of 20963855 is 55836902.

It is not a de Polignac number, because 20963855 - 2² = 20963851 is a prime.

It is a super-2 number, since 2×20963855² = 878966432922050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20963851) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16721 + ... + 17930.

It is an arithmetic number, because the mean of its divisors is an integer number (2304358).

Almost surely, 2^20963855 is an apocalyptic number.

20963855 is a deficient number, since it is larger than the sum of its proper divisors (6688441).

20963855 is a wasteful number, since it uses less digits than its factorization.

20963855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34678 (or 34667 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 38.

The square root of 20963855 is about 4578.6302536894. The cubic root of 20963855 is about 275.7340389361.

The spelling of 20963855 in words is "twenty million, nine hundred sixty-three thousand, eight hundred fifty-five".