158991864 has 64 divisors (see below), whose sum is σ = 406640640. Its totient is φ = 51788160.

The previous prime is 158991863. The next prime is 158991881. The reversal of 158991864 is 468199851.

158991864 is digitally balanced in base 2, 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 (158991863) 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, 326229 + ... + 326715.

It is an arithmetic number, because the mean of its divisors is an integer number (6353760).

Almost surely, 2^158991864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 158991864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (203320320).

158991864 is an abundant number, since it is smaller than the sum of its proper divisors (247648776).

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

158991864 is a wasteful number, since it uses less digits than its factorization.

158991864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780 (or 776 counting only the distinct ones).

The product of its digits is 622080, while the sum is 51.

The square root of 158991864 is about 12609.1975954063. The cubic root of 158991864 is about 541.7409109224.

The spelling of 158991864 in words is "one hundred fifty-eight million, nine hundred ninety-one thousand, eight hundred sixty-four".