20066400 has 144 divisors (see below), whose sum is σ = 72651600. Its totient is φ = 5345280.

The previous prime is 20066399. The next prime is 20066401. The reversal of 20066400 is 466002.

20066400 is a `hidden beast` number, since 2 + 0 + 0 + 664 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (20066399) and next prime (20066401).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20066401) 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, 21136 + ... + 22064.

It is an arithmetic number, because the mean of its divisors is an integer number (504525).

Almost surely, 2^20066400 is an apocalyptic number.

20066400 is a gapful number since it is divisible by the number (20) 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 20066400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36325800).

20066400 is an abundant number, since it is smaller than the sum of its proper divisors (52585200).

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

20066400 is a wasteful number, since it uses less digits than its factorization.

20066400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958 (or 939 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 20066400 is about 4479.5535491832. The cubic root of 20066400 is about 271.7418253831.

The spelling of 20066400 in words is "twenty million, sixty-six thousand, four hundred".