9961654591 has 32 divisors (see below), whose sum is σ = 12140679168. Its totient is φ = 7988872320.

The previous prime is 9961654531. The next prime is 9961654597. The reversal of 9961654591 is 1954561699.

It is a happy number.

9961654591 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9961654591 - 2⁷ = 9961654463 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9961654597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3130021 + ... + 3133201.

It is an arithmetic number, because the mean of its divisors is an integer number (379396224).

Almost surely, 2^9961654591 is an apocalyptic number.

9961654591 is a deficient number, since it is larger than the sum of its proper divisors (2179024577).

9961654591 is a wasteful number, since it uses less digits than its factorization.

9961654591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3631.

The product of its digits is 2624400, while the sum is 55.

The square root of 9961654591 is about 99808.0888054671. The cubic root of 9961654591 is about 2151.6774067394.

The spelling of 9961654591 in words is "nine billion, nine hundred sixty-one million, six hundred fifty-four thousand, five hundred ninety-one".