23531155440 has 160 divisors (see below), whose sum is σ = 79279717440. Its totient is φ = 5739061248.

The previous prime is 23531155391. The next prime is 23531155469. The reversal of 23531155440 is 4455113532.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 305484 + ... + 374676.

It is an arithmetic number, because the mean of its divisors is an integer number (495498234).

Almost surely, 2^23531155440 is an apocalyptic number.

23531155440 is a gapful number since it is divisible by the number (20) 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 23531155440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39639858720).

23531155440 is an abundant number, since it is smaller than the sum of its proper divisors (55748562000).

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

23531155440 is a wasteful number, since it uses less digits than its factorization.

23531155440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69331 (or 69325 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 33.

Adding to 23531155440 its reverse (4455113532), we get a palindrome (27986268972).

The spelling of 23531155440 in words is "twenty-three billion, five hundred thirty-one million, one hundred fifty-five thousand, four hundred forty".