385621681645 has 4 divisors (see below), whose sum is σ = 462746017980. Its totient is φ = 308497345312.

The previous prime is 385621681609. The next prime is 385621681649. The reversal of 385621681645 is 546186126583.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 258883545636 + 126738136009 = 508806^2 + 356003^2 .

It is a cyclic number.

It is not a de Polignac number, because 385621681645 - 2⁷ = 385621681517 is a prime.

It is a super-3 number, since 3×385621681645³ (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 (385621681649) 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, 38562168160 + ... + 38562168169.

It is an arithmetic number, because the mean of its divisors is an integer number (115686504495).

Almost surely, 2^385621681645 is an apocalyptic number.

It is an amenable number.

385621681645 is a deficient number, since it is larger than the sum of its proper divisors (77124336335).

385621681645 is an equidigital number, since it uses as much as digits as its factorization.

385621681645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77124336334.

The product of its digits is 8294400, while the sum is 55.

The spelling of 385621681645 in words is "three hundred eighty-five billion, six hundred twenty-one million, six hundred eighty-one thousand, six hundred forty-five".