9661744871 has 4 divisors (see below), whose sum is σ = 9747247152. Its totient is φ = 9576242592.

The previous prime is 9661744847. The next prime is 9661744879. The reversal of 9661744871 is 1784471669.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1784471669 = 29129 ⋅61261.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9661744871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9661744879) 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, 42750971 + ... + 42751196.

It is an arithmetic number, because the mean of its divisors is an integer number (2436811788).

Almost surely, 2^9661744871 is an apocalyptic number.

9661744871 is a deficient number, since it is larger than the sum of its proper divisors (85502281).

9661744871 is a wasteful number, since it uses less digits than its factorization.

9661744871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85502280.

The product of its digits is 2032128, while the sum is 53.

The square root of 9661744871 is about 98294.1751631296. The cubic root of 9661744871 is about 2129.8639124116.

The spelling of 9661744871 in words is "nine billion, six hundred sixty-one million, seven hundred forty-four thousand, eight hundred seventy-one".