3661013538 has 180 divisors, whose sum is σ = 10337016690. Its totient is φ = 965188224.

The previous prime is 3661013527. The next prime is 3661013539. The reversal of 3661013538 is 8353101663.

It is a happy number.

3661013538 is a `hidden beast` number, since 3 + 6 + 610 + 1 + 3 + 5 + 38 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 2860859169 + 800154369 = 53487^2 + 28287^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3661013539) by changing a digit.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 1340158 + ... + 1342886.

Almost surely, 2^3661013538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3661013538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5168508345).

3661013538 is an abundant number, since it is smaller than the sum of its proper divisors (6676003152).

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

3661013538 is a wasteful number, since it uses less digits than its factorization.

3661013538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2783 (or 2754 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 3661013538 is about 60506.3099023565. The cubic root of 3661013538 is about 1541.2287851165.

The spelling of 3661013538 in words is "three billion, six hundred sixty-one million, thirteen thousand, five hundred thirty-eight".