42785021817 has 12 divisors (see below), whose sum is σ = 63470873700. Its totient is φ = 27752446368.

The previous prime is 42785021761. The next prime is 42785021821. The reversal of 42785021817 is 71812058724.

42785021817 is a `hidden beast` number, since 427 + 8 + 5 + 0 + 218 + 1 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 37127123856 + 5657897961 = 192684^2 + 75219^2 .

It is not a de Polignac number, because 42785021817 - 2¹⁴ = 42785005433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42785021827) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64241442 + ... + 64242107.

It is an arithmetic number, because the mean of its divisors is an integer number (5289239475).

Almost surely, 2^42785021817 is an apocalyptic number.

It is an amenable number.

42785021817 is a deficient number, since it is larger than the sum of its proper divisors (20685851883).

42785021817 is a wasteful number, since it uses less digits than its factorization.

42785021817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128483592 (or 128483589 counting only the distinct ones).

The product of its (nonzero) digits is 250880, while the sum is 45.

The spelling of 42785021817 in words is "forty-two billion, seven hundred eighty-five million, twenty-one thousand, eight hundred seventeen".