20003864 has 16 divisors (see below), whose sum is σ = 37859400. Its totient is φ = 9908032.

The previous prime is 20003861. The next prime is 20003869. The reversal of 20003864 is 46830002.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20003861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10829 + ... + 12540.

Almost surely, 2^20003864 is an apocalyptic number.

It is an amenable number.

20003864 is a deficient number, since it is larger than the sum of its proper divisors (17855536).

20003864 is a wasteful number, since it uses less digits than its factorization.

20003864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23482 (or 23478 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 20003864 is about 4472.5679424688. The cubic root of 20003864 is about 271.4592413833.

Adding to 20003864 its reverse (46830002), we get a palindrome (66833866).

The spelling of 20003864 in words is "twenty million, three thousand, eight hundred sixty-four".