66231900 has 108 divisors (see below), whose sum is σ = 237279952. Its totient is φ = 15137280.

The previous prime is 66231889. The next prime is 66231901. The reversal of 66231900 is 913266.

It is a happy number.

It is a super-2 number, since 2×66231900² = 8773329155220000, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66231901) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1044 + ... + 11556.

Almost surely, 2^66231900 is an apocalyptic number.

66231900 is a gapful number since it is divisible by the number (60) 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 66231900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118639976).

66231900 is an abundant number, since it is smaller than the sum of its proper divisors (171048052).

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

66231900 is a wasteful number, since it uses less digits than its factorization.

66231900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10540 (or 10530 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 66231900 is about 8138.2983479349. The cubic root of 66231900 is about 404.5967637193.

The spelling of 66231900 in words is "sixty-six million, two hundred thirty-one thousand, nine hundred".