8478915781 has 16 divisors (see below), whose sum is σ = 9762054016. Its totient is φ = 7213841856.

The previous prime is 8478915773. The next prime is 8478915793. The reversal of 8478915781 is 1875198748.

It is a cyclic number.

It is not a de Polignac number, because 8478915781 - 2³ = 8478915773 is a prime.

It is a super-2 number, since 2×8478915781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8478915701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1224130 + ... + 1231036.

It is an arithmetic number, because the mean of its divisors is an integer number (610128376).

Almost surely, 2^8478915781 is an apocalyptic number.

It is an amenable number.

8478915781 is a deficient number, since it is larger than the sum of its proper divisors (1283138235).

8478915781 is a wasteful number, since it uses less digits than its factorization.

8478915781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8188.

The product of its digits is 4515840, while the sum is 58.

The square root of 8478915781 is about 92081.0283446053. The cubic root of 8478915781 is about 2039.1387320526.

The spelling of 8478915781 in words is "eight billion, four hundred seventy-eight million, nine hundred fifteen thousand, seven hundred eighty-one".