2158194040 has 64 divisors (see below), whose sum is σ = 5198256000. Its totient is φ = 803963520.

The previous prime is 2158194023. The next prime is 2158194041. The reversal of 2158194040 is 404918512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 2158193987 and 2158194005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2158194041) 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, 20775 + ... + 68905.

It is an arithmetic number, because the mean of its divisors is an integer number (81222750).

Almost surely, 2^2158194040 is an apocalyptic number.

2158194040 is a gapful number since it is divisible by the number (20) 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 2158194040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2599128000).

2158194040 is an abundant number, since it is smaller than the sum of its proper divisors (3040061960).

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

2158194040 is a wasteful number, since it uses less digits than its factorization.

2158194040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48220 (or 48216 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 2158194040 is about 46456.3670555501. The cubic root of 2158194040 is about 1292.3004521914.

The spelling of 2158194040 in words is "two billion, one hundred fifty-eight million, one hundred ninety-four thousand, forty".