11917810640 has 160 divisors (see below), whose sum is σ = 29690599680. Its totient is φ = 4439052288.

The previous prime is 11917810637. The next prime is 11917810643. The reversal of 11917810640 is 4601871911.

It is an interprime number because it is at equal distance from previous prime (11917810637) and next prime (11917810643).

It is a junction number, because it is equal to n+sod(n) for n = 11917810594 and 11917810603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11917810643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11148026 + ... + 11149094.

It is an arithmetic number, because the mean of its divisors is an integer number (185566248).

Almost surely, 2^11917810640 is an apocalyptic number.

11917810640 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 11917810640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14845299840).

11917810640 is an abundant number, since it is smaller than the sum of its proper divisors (17772789040).

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

11917810640 is a wasteful number, since it uses less digits than its factorization.

11917810640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1261 (or 1255 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 38.

The spelling of 11917810640 in words is "eleven billion, nine hundred seventeen million, eight hundred ten thousand, six hundred forty".