1991636929152 has 384 divisors, whose sum is σ = 6425715114000. Its totient is φ = 587891146752.

The previous prime is 1991636929099. The next prime is 1991636929207. The reversal of 1991636929152 is 2519296361991.

1991636929152 is a `hidden beast` number, since 1 + 99 + 16 + 369 + 29 + 152 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 382250373696 + 1609386555456 = 618264^2 + 1268616^2 .

It is a tau number, because it is divible by the number of its divisors (384).

It is a self number, because there is not a number n which added to its sum of digits gives 1991636929152.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 68171124 + ... + 68200332.

Almost surely, 2^{1991636929152} is an apocalyptic number.

1991636929152 is a gapful number since it is divisible by the number (12) 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 1991636929152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3212857557000).

1991636929152 is an abundant number, since it is smaller than the sum of its proper divisors (4434078184848).

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

1991636929152 is a wasteful number, since it uses less digits than its factorization.

1991636929152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29428 (or 29413 counting only the distinct ones).

The product of its digits is 14171760, while the sum is 63.

The spelling of 1991636929152 in words is "one trillion, nine hundred ninety-one billion, six hundred thirty-six million, nine hundred twenty-nine thousand, one hundred fifty-two".