20023864 has 16 divisors (see below), whose sum is σ = 42908400. Its totient is φ = 8581632.

The previous prime is 20023859. The next prime is 20023889. The reversal of 20023864 is 46832002.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 178729 + ... + 178840.

It is an arithmetic number, because the mean of its divisors is an integer number (2681775).

Almost surely, 2^20023864 is an apocalyptic number.

It is an amenable number.

20023864 is an abundant number, since it is smaller than the sum of its proper divisors (22884536).

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

20023864 is a wasteful number, since it uses less digits than its factorization.

20023864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357582 (or 357578 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 20023864 is about 4474.8032358976. The cubic root of 20023864 is about 271.5496801847.

Adding to 20023864 its reverse (46832002), we get a palindrome (66855866).

The spelling of 20023864 in words is "twenty million, twenty-three thousand, eight hundred sixty-four".