394821789645 has 8 divisors (see below), whose sum is σ = 631714863456. Its totient is φ = 210571621136.

The previous prime is 394821789643. The next prime is 394821789647. The reversal of 394821789645 is 546987128493.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (394821789643) and next prime (394821789647).

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

It is a cyclic number.

It is not a de Polignac number, because 394821789645 - 2¹ = 394821789643 is a prime.

It is a super-3 number, since 3×394821789645³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394821789643) 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, 13160726307 + ... + 13160726336.

It is an arithmetic number, because the mean of its divisors is an integer number (78964357932).

Almost surely, 2^394821789645 is an apocalyptic number.

It is an amenable number.

394821789645 is a deficient number, since it is larger than the sum of its proper divisors (236893073811).

394821789645 is a wasteful number, since it uses less digits than its factorization.

394821789645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26321452651.

The product of its digits is 104509440, while the sum is 66.

The spelling of 394821789645 in words is "three hundred ninety-four billion, eight hundred twenty-one million, seven hundred eighty-nine thousand, six hundred forty-five".