11731539840 has 128 divisors (see below), whose sum is σ = 37439932320. Its totient is φ = 3124592640.

The previous prime is 11731539829. The next prime is 11731539847. The reversal of 11731539840 is 4893513711.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 11731539792 and 11731539801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11731539847) 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, 1795780 + ... + 1802300.

Almost surely, 2^11731539840 is an apocalyptic number.

11731539840 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 11731539840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18719966160).

11731539840 is an abundant number, since it is smaller than the sum of its proper divisors (25708392480).

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

11731539840 is an equidigital number, since it uses as much as digits as its factorization.

11731539840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7480 (or 7468 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 42.

The spelling of 11731539840 in words is "eleven billion, seven hundred thirty-one million, five hundred thirty-nine thousand, eight hundred forty".