18941091840 has 672 divisors, whose sum is σ = 74709625536. Its totient is φ = 4565237760.

The previous prime is 18941091839. The next prime is 18941091913. The reversal of 18941091840 is 4819014981.

18941091840 is a `hidden beast` number, since 189 + 410 + 9 + 18 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 109485994 + ... + 109486166.

It is an arithmetic number, because the mean of its divisors is an integer number (111175038).

Almost surely, 2^18941091840 is an apocalyptic number.

18941091840 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 18941091840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37354812768).

18941091840 is an abundant number, since it is smaller than the sum of its proper divisors (55768533696).

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

18941091840 is an equidigital number, since it uses as much as digits as its factorization.

18941091840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230 (or 194 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 45.

The spelling of 18941091840 in words is "eighteen billion, nine hundred forty-one million, ninety-one thousand, eight hundred forty".