10643820561 has 48 divisors (see below), whose sum is σ = 17519628672. Its totient is φ = 6163872000.

The previous prime is 10643820541. The next prime is 10643820563. The reversal of 10643820561 is 16502834601.

It is a happy number.

10643820561 is a `hidden beast` number, since 1 + 0 + 64 + 38 + 2 + 0 + 561 = 666.

It is not a de Polignac number, because 10643820561 - 2⁵ = 10643820529 is a prime.

It is a super-2 number, since 2×10643820561² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (10643820563) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2960581 + ... + 2964173.

It is an arithmetic number, because the mean of its divisors is an integer number (364992264).

Almost surely, 2^10643820561 is an apocalyptic number.

10643820561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

10643820561 is a deficient number, since it is larger than the sum of its proper divisors (6875808111).

10643820561 is a wasteful number, since it uses less digits than its factorization.

10643820561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4934 (or 4931 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 10643820561 in words is "ten billion, six hundred forty-three million, eight hundred twenty thousand, five hundred sixty-one".