991395629952 has 512 divisors, whose sum is σ = 3491203645440. Its totient is φ = 242025062400.

The previous prime is 991395629951. The next prime is 991395629969. The reversal of 991395629952 is 259926593199.

It is a Harshad number since it is a multiple of its sum of digits (69).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991395629951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 24895177 + ... + 24934967.

It is an arithmetic number, because the mean of its divisors is an integer number (6818757120).

Almost surely, 2^991395629952 is an apocalyptic number.

991395629952 is a gapful number since it is divisible by the number (92) 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 991395629952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1745601822720).

991395629952 is an abundant number, since it is smaller than the sum of its proper divisors (2499808015488).

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

991395629952 is a wasteful number, since it uses less digits than its factorization.

991395629952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39882 (or 39870 counting only the distinct ones).

The product of its digits is 106288200, while the sum is 69.

The spelling of 991395629952 in words is "nine hundred ninety-one billion, three hundred ninety-five million, six hundred twenty-nine thousand, nine hundred fifty-two".