1991634432 has 160 divisors (see below), whose sum is σ = 5533169664. Its totient is φ = 635904000.

The previous prime is 1991634431. The next prime is 1991634443. The reversal of 1991634432 is 2344361991.

1991634432 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991634431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7189878 + ... + 7190154.

Almost surely, 2^1991634432 is an apocalyptic number.

1991634432 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 1991634432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2766584832).

1991634432 is an abundant number, since it is smaller than the sum of its proper divisors (3541535232).

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

1991634432 is a wasteful number, since it uses less digits than its factorization.

1991634432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480 (or 464 counting only the distinct ones).

The product of its digits is 139968, while the sum is 42.

The square root of 1991634432 is about 44627.7316474857. The cubic root of 1991634432 is about 1258.1619357426.

The spelling of 1991634432 in words is "one billion, nine hundred ninety-one million, six hundred thirty-four thousand, four hundred thirty-two".