845668993 has 8 divisors (see below), whose sum is σ = 932933736. Its totient is φ = 761577600.

The previous prime is 845668981. The next prime is 845669021. The reversal of 845668993 is 399866548.

It can be written as a sum of positive squares in 4 ways, for example, as 25877569 + 819791424 = 5087^2 + 28632^2 .

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-845668993 is a prime.

It is a super-4 number, since 4×845668993⁴ (a number of 37 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (845668963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 792778 + ... + 793843.

It is an arithmetic number, because the mean of its divisors is an integer number (116616717).

Almost surely, 2^845668993 is an apocalyptic number.

It is an amenable number.

845668993 is a deficient number, since it is larger than the sum of its proper divisors (87264743).

845668993 is a wasteful number, since it uses less digits than its factorization.

845668993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1586675.

The product of its digits is 11197440, while the sum is 58.

The square root of 845668993 is about 29080.3884602665. The cubic root of 845668993 is about 945.6566241675.

The spelling of 845668993 in words is "eight hundred forty-five million, six hundred sixty-eight thousand, nine hundred ninety-three".