31109105664 has 576 divisors, whose sum is σ = 117195361920. Its totient is φ = 7714897920.

The previous prime is 31109105623. The next prime is 31109105693. The reversal of 31109105664 is 46650190113.

31109105664 is a `hidden beast` number, since 3 + 1 + 1 + 0 + 91 + 0 + 566 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 28513759 + ... + 28514849.

It is an arithmetic number, because the mean of its divisors is an integer number (203464170).

Almost surely, 2^31109105664 is an apocalyptic number.

31109105664 is a gapful number since it is divisible by the number (34) 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 31109105664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (58597680960).

31109105664 is an abundant number, since it is smaller than the sum of its proper divisors (86086256256).

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

31109105664 is a wasteful number, since it uses less digits than its factorization.

31109105664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1156 (or 1133 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

Adding to 31109105664 its reverse (46650190113), we get a palindrome (77759295777).

The spelling of 31109105664 in words is "thirty-one billion, one hundred nine million, one hundred five thousand, six hundred sixty-four".