2158499989 has 8 divisors (see below), whose sum is σ = 2191467672. Its totient is φ = 2125624320.

The previous prime is 2158499971. The next prime is 2158499999. The reversal of 2158499989 is 9899948512.

It can be written as a sum of positive squares in 4 ways, for example, as 476679889 + 1681820100 = 21833^2 + 41010^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2158499989 - 2⁹ = 2158499477 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2158499989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2158499999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25029 + ... + 70309.

It is an arithmetic number, because the mean of its divisors is an integer number (273933459).

Almost surely, 2^2158499989 is an apocalyptic number.

It is an amenable number.

2158499989 is a deficient number, since it is larger than the sum of its proper divisors (32967683).

2158499989 is an equidigital number, since it uses as much as digits as its factorization.

2158499989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46007.

The product of its digits is 16796160, while the sum is 64.

The square root of 2158499989 is about 46459.6598028871. The cubic root of 2158499989 is about 1292.3615154912.

The spelling of 2158499989 in words is "two billion, one hundred fifty-eight million, four hundred ninety-nine thousand, nine hundred eighty-nine".