1645623221326 has 24 divisors (see below), whose sum is σ = 2925622809720. Its totient is φ = 691960166352.

The previous prime is 1645623221311. The next prime is 1645623221327. The reversal of 1645623221326 is 6231223265461.

It is a super-2 number, since 2×1645623221326² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645623221327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 158410596 + ... + 158420983.

It is an arithmetic number, because the mean of its divisors is an integer number (121900950405).

Almost surely, 2^{1645623221326} is an apocalyptic number.

1645623221326 is a deficient number, since it is larger than the sum of its proper divisors (1279999588394).

1645623221326 is a wasteful number, since it uses less digits than its factorization.

1645623221326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316831648 (or 316831641 counting only the distinct ones).

The product of its digits is 622080, while the sum is 43.

Adding to 1645623221326 its reverse (6231223265461), we get a palindrome (7876846486787).

The spelling of 1645623221326 in words is "one trillion, six hundred forty-five billion, six hundred twenty-three million, two hundred twenty-one thousand, three hundred twenty-six".