8320047781 has 4 divisors (see below), whose sum is σ = 8461065600. Its totient is φ = 8179029964.

The previous prime is 8320047773. The next prime is 8320047793. The reversal of 8320047781 is 1877400238.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8320047781 - 2³ = 8320047773 is a prime.

It is a super-2 number, since 2×8320047781² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8320047721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70508821 + ... + 70508938.

It is an arithmetic number, because the mean of its divisors is an integer number (2115266400).

Almost surely, 2^8320047781 is an apocalyptic number.

It is an amenable number.

8320047781 is a deficient number, since it is larger than the sum of its proper divisors (141017819).

8320047781 is a wasteful number, since it uses less digits than its factorization.

8320047781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141017818.

The product of its (nonzero) digits is 75264, while the sum is 40.

The square root of 8320047781 is about 91214.2959244876. The cubic root of 8320047781 is about 2026.3226866209.

The spelling of 8320047781 in words is "eight billion, three hundred twenty million, forty-seven thousand, seven hundred eighty-one".