20693904 has 120 divisors (see below), whose sum is σ = 67287360. Its totient is φ = 5364480.

The previous prime is 20693891. The next prime is 20693909. The reversal of 20693904 is 40939602.

It is a super-2 number, since 2×20693904² = 856475325522432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (20693909) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40402 + ... + 40910.

It is an arithmetic number, because the mean of its divisors is an integer number (560728).

Almost surely, 2^20693904 is an apocalyptic number.

20693904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20693904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33643680).

20693904 is an abundant number, since it is smaller than the sum of its proper divisors (46593456).

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

20693904 is a wasteful number, since it uses less digits than its factorization.

20693904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 549 (or 532 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 33.

The square root of 20693904 is about 4549.0552865403. The cubic root of 20693904 is about 274.5453821935.

The spelling of 20693904 in words is "twenty million, six hundred ninety-three thousand, nine hundred four".