7871540785 has 8 divisors (see below), whose sum is σ = 9543229416. Its totient is φ = 6232312320.

The previous prime is 7871540779. The next prime is 7871540813. The reversal of 7871540785 is 5870451787.

It can be written as a sum of positive squares in 4 ways, for example, as 1070074944 + 6801465841 = 32712^2 + 82471^2 .

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

It is not a de Polignac number, because 7871540785 - 2¹⁷ = 7871409713 is a prime.

It is a super-2 number, since 2×7871540785² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 8114506 + ... + 8115475.

It is an arithmetic number, because the mean of its divisors is an integer number (1192903677).

Almost surely, 2^7871540785 is an apocalyptic number.

It is an amenable number.

7871540785 is a deficient number, since it is larger than the sum of its proper divisors (1671688631).

7871540785 is a wasteful number, since it uses less digits than its factorization.

7871540785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16230083.

The product of its (nonzero) digits is 2195200, while the sum is 52.

The square root of 7871540785 is about 88721.7041371501. The cubic root of 7871540785 is about 1989.2372509264.

The spelling of 7871540785 in words is "seven billion, eight hundred seventy-one million, five hundred forty thousand, seven hundred eighty-five".