10000661565 has 16 divisors (see below), whose sum is σ = 16019837568. Its totient is φ = 5327426496.

The previous prime is 10000661543. The next prime is 10000661591. The reversal of 10000661565 is 56516600001.

It is not a de Polignac number, because 10000661565 - 2⁶ = 10000661501 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 378009 + ... + 403598.

It is an arithmetic number, because the mean of its divisors is an integer number (1001239848).

Almost surely, 2^10000661565 is an apocalyptic number.

10000661565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

10000661565 is a deficient number, since it is larger than the sum of its proper divisors (6019176003).

10000661565 is an equidigital number, since it uses as much as digits as its factorization.

10000661565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 782468.

The product of its (nonzero) digits is 5400, while the sum is 30.

The spelling of 10000661565 in words is "ten billion, six hundred sixty-one thousand, five hundred sixty-five".