991342470688416 has 432 divisors, whose sum is σ = 3591265383748224. Its totient is φ = 253864904832000.

The previous prime is 991342470688369. The next prime is 991342470688541. The reversal of 991342470688416 is 614886074243199.

991342470688416 is a `hidden beast` number, since 9 + 9 + 1 + 3 + 4 + 2 + 470 + 68 + 84 + 16 = 666.

It is a super-2 number, since 2×991342470688416² (a number of 31 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 11299875 + ... + 45938786.

It is an arithmetic number, because the mean of its divisors is an integer number (8313114314232).

Almost surely, 2^{991342470688416} is an apocalyptic number.

991342470688416 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 991342470688416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1795632691874112).

991342470688416 is an abundant number, since it is smaller than the sum of its proper divisors (2599922913059808).

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

991342470688416 is a wasteful number, since it uses less digits than its factorization.

991342470688416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57238777 (or 57238755 counting only the distinct ones).

The product of its (nonzero) digits is 501645312, while the sum is 72.

The spelling of 991342470688416 in words is "nine hundred ninety-one trillion, three hundred forty-two billion, four hundred seventy million, six hundred eighty-eight thousand, four hundred sixteen".