11601643780 has 48 divisors (see below), whose sum is σ = 25084964016. Its totient is φ = 4503859200.

The previous prime is 11601643759. The next prime is 11601643783. The reversal of 11601643780 is 8734610611.

It can be written as a sum of positive squares in 8 ways, for example, as 2224820224 + 9376823556 = 47168^2 + 96834^2 .

It is a Harshad number since it is a multiple of its sum of digits (37).

It is not an unprimeable number, because it can be changed into a prime (11601643783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 277192 + ... + 316288.

It is an arithmetic number, because the mean of its divisors is an integer number (522603417).

Almost surely, 2^11601643780 is an apocalyptic number.

11601643780 is a gapful number since it is divisible by the number (10) 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 11601643780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12542482008).

11601643780 is an abundant number, since it is smaller than the sum of its proper divisors (13483320236).

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

11601643780 is a wasteful number, since it uses less digits than its factorization.

11601643780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39544 (or 39542 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The spelling of 11601643780 in words is "eleven billion, six hundred one million, six hundred forty-three thousand, seven hundred eighty".