1645533563643 has 12 divisors (see below), whose sum is σ = 2516698391688. Its totient is φ = 1032491647680.

The previous prime is 1645533563573. The next prime is 1645533563683. The reversal of 1645533563643 is 3463653355461.

1645533563643 is a `hidden beast` number, since 1 + 6 + 4 + 5 + 5 + 33 + 563 + 6 + 43 = 666.

It is not a de Polignac number, because 1645533563643 - 2¹⁰ = 1645533562619 is a prime.

It is a super-2 number, since 2×1645533563643² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1645533563643.

It is not an unprimeable number, because it can be changed into a prime (1645533563683) 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, 5377560513 + ... + 5377560818.

It is an arithmetic number, because the mean of its divisors is an integer number (209724865974).

Almost surely, 2^{1645533563643} is an apocalyptic number.

1645533563643 is a deficient number, since it is larger than the sum of its proper divisors (871164828045).

1645533563643 is a wasteful number, since it uses less digits than its factorization.

1645533563643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10755121354 (or 10755121351 counting only the distinct ones).

The product of its digits is 34992000, while the sum is 54.

The spelling of 1645533563643 in words is "one trillion, six hundred forty-five billion, five hundred thirty-three million, five hundred sixty-three thousand, six hundred forty-three".