2115512640 has 280 divisors, whose sum is σ = 7969572072. Its totient is φ = 530841600.

The previous prime is 2115512599. The next prime is 2115512717. The reversal of 2115512640 is 462155112.

2115512640 is a `hidden beast` number, since 2 + 1 + 1 + 5 + 5 + 12 + 640 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 501401664 + 1614110976 = 22392^2 + 40176^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 438240 + ... + 443040.

Almost surely, 2^2115512640 is an apocalyptic number.

2115512640 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 2115512640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3984786036).

2115512640 is an abundant number, since it is smaller than the sum of its proper divisors (5854059432).

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

2115512640 is a wasteful number, since it uses less digits than its factorization.

2115512640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4847 (or 4828 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 2115512640 is about 45994.7023036349. The cubic root of 2115512640 is about 1283.7246330618.

Adding to 2115512640 its reverse (462155112), we get a palindrome (2577667752).

The spelling of 2115512640 in words is "two billion, one hundred fifteen million, five hundred twelve thousand, six hundred forty".