12491377920 has 324 divisors, whose sum is σ = 50277279780. Its totient is φ = 2855043072.

The previous prime is 12491377919. The next prime is 12491377937. The reversal of 12491377920 is 2977319421.

12491377920 is a `hidden beast` number, since 1 + 2 + 491 + 3 + 77 + 92 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8914381056 + 3576996864 = 94416^2 + 59808^2 .

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 (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 553416 + ... + 575544.

Almost surely, 2^12491377920 is an apocalyptic number.

12491377920 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 12491377920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25138639890).

12491377920 is an abundant number, since it is smaller than the sum of its proper divisors (37785901860).

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

12491377920 is a wasteful number, since it uses less digits than its factorization.

12491377920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22170 (or 22146 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The spelling of 12491377920 in words is "twelve billion, four hundred ninety-one million, three hundred seventy-seven thousand, nine hundred twenty".