2158900 has 18 divisors (see below), whose sum is σ = 4685030. Its totient is φ = 863520.

The previous prime is 2158889. The next prime is 2158903. The reversal of 2158900 is 98512.

It can be written as a sum of positive squares in 3 ways, for example, as 119716 + 2039184 = 346^2 + 1428^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2158903) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10695 + ... + 10894.

2^2158900 is an apocalyptic number.

2158900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2158900 is an abundant number, since it is smaller than the sum of its proper divisors (2526130).

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

2158900 is a wasteful number, since it uses less digits than its factorization.

2158900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21603 (or 21596 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 2158900 is about 1469.3195704135. The cubic root of 2158900 is about 129.2441343596.

The spelling of 2158900 in words is "two million, one hundred fifty-eight thousand, nine hundred".