660661236 has 72 divisors (see below), whose sum is σ = 1764628320. Its totient is φ = 207831744.

The previous prime is 660661231. The next prime is 660661241. The reversal of 660661236 is 632166066.

660661236 is a `hidden beast` number, since 6 + 6 + 0 + 6 + 612 + 36 = 666.

It is an interprime number because it is at equal distance from previous prime (660661231) and next prime (660661241).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 660661236.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660661231) 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, 191866 + ... + 195278.

Almost surely, 2^660661236 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660661236, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (882314160).

660661236 is an abundant number, since it is smaller than the sum of its proper divisors (1103967084).

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

660661236 is a wasteful number, since it uses less digits than its factorization.

660661236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3725 (or 3720 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The square root of 660661236 is about 25703.3312237928. The cubic root of 660661236 is about 870.9494351607.

The spelling of 660661236 in words is "six hundred sixty million, six hundred sixty-one thousand, two hundred thirty-six".