9891439012 has 48 divisors (see below), whose sum is σ = 21561386112. Its totient is φ = 3865939200.

The previous prime is 9891439009. The next prime is 9891439021. The reversal of 9891439012 is 2109341989.

It is a happy number.

It is a super-2 number, since 2×9891439012² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 133489 + ... + 193912.

It is an arithmetic number, because the mean of its divisors is an integer number (449195544).

Almost surely, 2^9891439012 is an apocalyptic number.

It is an amenable number.

9891439012 is an abundant number, since it is smaller than the sum of its proper divisors (11669947100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9891439012 is a wasteful number, since it uses less digits than its factorization.

9891439012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327508 (or 327506 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 46.

The square root of 9891439012 is about 99455.7138227865. The cubic root of 9891439012 is about 2146.6100543926.

The spelling of 9891439012 in words is "nine billion, eight hundred ninety-one million, four hundred thirty-nine thousand, twelve".