212166660 has 96 divisors (see below), whose sum is σ = 606477312. Its totient is φ = 55411200.

The previous prime is 212166649. The next prime is 212166667. The reversal of 212166660 is 66661212.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (212166667) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 951309 + ... + 951531.

It is an arithmetic number, because the mean of its divisors is an integer number (6317472).

Almost surely, 2^212166660 is an apocalyptic number.

212166660 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 212166660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303238656).

212166660 is an abundant number, since it is smaller than the sum of its proper divisors (394310652).

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

212166660 is a wasteful number, since it uses less digits than its factorization.

212166660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493 (or 491 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 212166660 is about 14565.9417821163. The cubic root of 212166660 is about 596.4294046762.

The spelling of 212166660 in words is "two hundred twelve million, one hundred sixty-six thousand, six hundred sixty".