991067616 has 192 divisors, whose sum is σ = 3604124160. Its totient is φ = 257402880.

The previous prime is 991067593. The next prime is 991067641. The reversal of 991067616 is 616760199.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59080 + ... + 73976.

It is an arithmetic number, because the mean of its divisors is an integer number (18771480).

Almost surely, 2^991067616 is an apocalyptic number.

991067616 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 991067616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1802062080).

991067616 is an abundant number, since it is smaller than the sum of its proper divisors (2613056544).

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

991067616 is a wasteful number, since it uses less digits than its factorization.

991067616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14934 (or 14920 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 991067616 is about 31481.2264055897. The cubic root of 991067616 is about 997.0136291336.

The spelling of 991067616 in words is "nine hundred ninety-one million, sixty-seven thousand, six hundred sixteen".