2115709638 has 32 divisors (see below), whose sum is σ = 4991907840. Its totient is φ = 584988480.

The previous prime is 2115709633. The next prime is 2115709639. The reversal of 2115709638 is 8369075112.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2115709638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2115709633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 811183 + ... + 813786.

It is an arithmetic number, because the mean of its divisors is an integer number (155997120).

Almost surely, 2^2115709638 is an apocalyptic number.

2115709638 is an abundant number, since it is smaller than the sum of its proper divisors (2876198202).

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

2115709638 is a wasteful number, since it uses less digits than its factorization.

2115709638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1625012.

The product of its (nonzero) digits is 90720, while the sum is 42.

The square root of 2115709638 is about 45996.8437830249. The cubic root of 2115709638 is about 1283.7644789335.

The spelling of 2115709638 in words is "two billion, one hundred fifteen million, seven hundred nine thousand, six hundred thirty-eight".