2138218740 has 144 divisors (see below), whose sum is σ = 7506670080. Its totient is φ = 482526720.

The previous prime is 2138218727. The next prime is 2138218763. The reversal of 2138218740 is 478128312.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2138218695 and 2138218704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 88800 + ... + 110280.

Almost surely, 2^2138218740 is an apocalyptic number.

2138218740 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 2138218740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3753335040).

2138218740 is an abundant number, since it is smaller than the sum of its proper divisors (5368451340).

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

2138218740 is a wasteful number, since it uses less digits than its factorization.

2138218740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21582 (or 21577 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 2138218740 is about 46240.8773705690. The cubic root of 2138218740 is about 1288.3010987031.

The spelling of 2138218740 in words is "two billion, one hundred thirty-eight million, two hundred eighteen thousand, seven hundred forty".