166213540 has 12 divisors (see below), whose sum is σ = 349048476. Its totient is φ = 66485408.

The previous prime is 166213519. The next prime is 166213547. The reversal of 166213540 is 45312661.

166213540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 117548964 + 48664576 = 10842^2 + 6976^2 .

It is a junction number, because it is equal to n+sod(n) for n = 166213499 and 166213508.

It is not an unprimeable number, because it can be changed into a prime (166213547) 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, 4155319 + ... + 4155358.

It is an arithmetic number, because the mean of its divisors is an integer number (29087373).

Almost surely, 2^166213540 is an apocalyptic number.

166213540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

166213540 is an abundant number, since it is smaller than the sum of its proper divisors (182834936).

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

166213540 is a wasteful number, since it uses less digits than its factorization.

166213540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8310686 (or 8310684 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 166213540 is about 12892.3830225447. The cubic root of 166213540 is about 549.8220250598.

It can be divided in two parts, 166213 and 540, that added together give a triangular number (166753 = T₅₇₇).

The spelling of 166213540 in words is "one hundred sixty-six million, two hundred thirteen thousand, five hundred forty".