108991481781 has 64 divisors (see below), whose sum is σ = 187157626880. Its totient is φ = 54873054720.

The previous prime is 108991481779. The next prime is 108991481791. The reversal of 108991481781 is 187184199801.

It is not a de Polignac number, because 108991481781 - 2¹ = 108991481779 is a prime.

It is a super-2 number, since 2×108991481781² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (108991481741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 529590 + ... + 706008.

It is an arithmetic number, because the mean of its divisors is an integer number (2924337920).

Almost surely, 2^108991481781 is an apocalyptic number.

It is an amenable number.

108991481781 is a deficient number, since it is larger than the sum of its proper divisors (78166145099).

108991481781 is a wasteful number, since it uses less digits than its factorization.

108991481781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176546.

The product of its (nonzero) digits is 1161216, while the sum is 57.

The spelling of 108991481781 in words is "one hundred eight billion, nine hundred ninety-one million, four hundred eighty-one thousand, seven hundred eighty-one".