9909387961 has 8 divisors (see below), whose sum is σ = 10815933024. Its totient is φ = 9003791520.

The previous prime is 9909387959. The next prime is 9909388033. The reversal of 9909387961 is 1697839099.

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

It is a cyclic number.

It is not a de Polignac number, because 9909387961 - 2¹ = 9909387959 is a prime.

It is a super-2 number, since 2×9909387961² (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 9909387961.

It is not an unprimeable number, because it can be changed into a prime (9909387361) 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, 215220 + ... + 257173.

It is an arithmetic number, because the mean of its divisors is an integer number (1351991628).

Almost surely, 2^9909387961 is an apocalyptic number.

It is an amenable number.

9909387961 is a deficient number, since it is larger than the sum of its proper divisors (906545063).

9909387961 is a wasteful number, since it uses less digits than its factorization.

9909387961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474311.

The product of its (nonzero) digits is 6613488, while the sum is 61.

The square root of 9909387961 is about 99545.9088109602. The cubic root of 9909387961 is about 2147.9076786222.

It can be divided in two parts, 990938 and 7961, that added together give a palindrome (998899).

The spelling of 9909387961 in words is "nine billion, nine hundred nine million, three hundred eighty-seven thousand, nine hundred sixty-one".