2138864 has 60 divisors (see below), whose sum is σ = 5173776. Its totient is φ = 838656.

The previous prime is 2138861. The next prime is 2138867. The reversal of 2138864 is 4688312.

It is an interprime number because it is at equal distance from previous prime (2138861) and next prime (2138867).

It is a d-powerful number, because it can be written as 2¹³ + 1 + 3⁶ + 8⁵ + 8⁷ + 6 + 4² .

It is a self number, because there is not a number n which added to its sum of digits gives 2138864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2138861) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18872 + ... + 18984.

2^2138864 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 2138864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2586888).

2138864 is an abundant number, since it is smaller than the sum of its proper divisors (3034912).

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

2138864 is a wasteful number, since it uses less digits than its factorization.

2138864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154 (or 135 counting only the distinct ones).

The product of its digits is 9216, while the sum is 32.

The square root of 2138864 is about 1462.4855554842. The cubic root of 2138864 is about 128.8430677831.

The spelling of 2138864 in words is "two million, one hundred thirty-eight thousand, eight hundred sixty-four".