11685420721640 has 16 divisors (see below), whose sum is σ = 26292196623780. Its totient is φ = 4674168288640.

The previous prime is 11685420721603. The next prime is 11685420721643. The reversal of 11685420721640 is 4612702458611.

11685420721640 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 11637527149924 + 47893571716 = 3411382^2 + 218846^2 .

It is not an unprimeable number, because it can be changed into a prime (11685420721643) 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, 146067758981 + ... + 146067759060.

Almost surely, 2^{11685420721640} is an apocalyptic number.

11685420721640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11685420721640 is an abundant number, since it is smaller than the sum of its proper divisors (14606775902140).

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

11685420721640 is a wasteful number, since it uses less digits than its factorization.

11685420721640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292135518052 (or 292135518048 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 47.

The spelling of 11685420721640 in words is "eleven trillion, six hundred eighty-five billion, four hundred twenty million, seven hundred twenty-one thousand, six hundred forty".