8939245781 has 8 divisors (see below), whose sum is σ = 9036977880. Its totient is φ = 8841627648.

The previous prime is 8939245741. The next prime is 8939245787. The reversal of 8939245781 is 1875429398.

It can be written as a sum of positive squares in 4 ways, for example, as 1831069681 + 7108176100 = 42791^2 + 84310^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8939245781 is a prime.

It is a super-2 number, since 2×8939245781² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8939245787) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 134285 + ... + 189501.

It is an arithmetic number, because the mean of its divisors is an integer number (1129622235).

Almost surely, 2^8939245781 is an apocalyptic number.

It is an amenable number.

8939245781 is a deficient number, since it is larger than the sum of its proper divisors (97732099).

8939245781 is a wasteful number, since it uses less digits than its factorization.

8939245781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56983.

The product of its digits is 4354560, while the sum is 56.

The square root of 8939245781 is about 94547.5847444026. The cubic root of 8939245781 is about 2075.3927378547.

The spelling of 8939245781 in words is "eight billion, nine hundred thirty-nine million, two hundred forty-five thousand, seven hundred eighty-one".