12156660 has 36 divisors (see below), whose sum is σ = 36875748. Its totient is φ = 3241728.

The previous prime is 12156643. The next prime is 12156671. The reversal of 12156660 is 6665121.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 2196324 + 9960336 = 1482^2 + 3156^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33589 + ... + 33948.

Almost surely, 2^12156660 is an apocalyptic number.

12156660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12156660 is an abundant number, since it is smaller than the sum of its proper divisors (24719088).

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

12156660 is a wasteful number, since it uses less digits than its factorization.

12156660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67552 (or 67547 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 12156660 is about 3486.6402165982. The cubic root of 12156660 is about 229.9348271550.

It can be divided in two parts, 1215 and 6660, that added together give a triangular number (7875 = T₁₂₅).

The spelling of 12156660 in words is "twelve million, one hundred fifty-six thousand, six hundred sixty".