10661813639 has 4 divisors (see below), whose sum is σ = 10662151224. Its totient is φ = 10661476056.

The previous prime is 10661813597. The next prime is 10661813683. The reversal of 10661813639 is 93631816601.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 10661813639 - 2²⁸ = 10393378183 is a prime.

It is a super-2 number, since 2×10661813639² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 10661813639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10661813689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115892 + ... + 186425.

It is an arithmetic number, because the mean of its divisors is an integer number (2665537806).

Almost surely, 2^10661813639 is an apocalyptic number.

10661813639 is a deficient number, since it is larger than the sum of its proper divisors (337585).

10661813639 is an equidigital number, since it uses as much as digits as its factorization.

10661813639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337584.

The product of its (nonzero) digits is 139968, while the sum is 44.

The spelling of 10661813639 in words is "ten billion, six hundred sixty-one million, eight hundred thirteen thousand, six hundred thirty-nine".