10005550661 has 4 divisors (see below), whose sum is σ = 10249588524. Its totient is φ = 9761512800.

The previous prime is 10005550657. The next prime is 10005550691. The reversal of 10005550661 is 16605550001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16605550001 = 479 ⋅34667119.

It can be written as a sum of positive squares in 2 ways, for example, as 2297764225 + 7707786436 = 47935^2 + 87794^2 .

It is a cyclic number.

It is not a de Polignac number, because 10005550661 - 2² = 10005550657 is a prime.

It is a super-2 number, since 2×10005550661² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10005550691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122018870 + ... + 122018951.

It is an arithmetic number, because the mean of its divisors is an integer number (2562397131).

Almost surely, 2^10005550661 is an apocalyptic number.

It is an amenable number.

10005550661 is a deficient number, since it is larger than the sum of its proper divisors (244037863).

10005550661 is an equidigital number, since it uses as much as digits as its factorization.

10005550661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244037862.

The product of its (nonzero) digits is 4500, while the sum is 29.

The spelling of 10005550661 in words is "ten billion, five million, five hundred fifty thousand, six hundred sixty-one".