9961000555 has 8 divisors (see below), whose sum is σ = 13039855344. Its totient is φ = 7244364000.

The previous prime is 9961000537. The next prime is 9961000559. The reversal of 9961000555 is 5550001699.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-9961000555 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9961000559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90554496 + ... + 90554605.

It is an arithmetic number, because the mean of its divisors is an integer number (1629981918).

Almost surely, 2^9961000555 is an apocalyptic number.

9961000555 is a deficient number, since it is larger than the sum of its proper divisors (3078854789).

9961000555 is a wasteful number, since it uses less digits than its factorization.

9961000555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181109117.

The product of its (nonzero) digits is 60750, while the sum is 40.

The square root of 9961000555 is about 99804.8122837772. The cubic root of 9961000555 is about 2151.6303159918.

The spelling of 9961000555 in words is "nine billion, nine hundred sixty-one million, five hundred fifty-five", and thus it is an aban number.