2605638540 has 48 divisors (see below), whose sum is σ = 7299855360. Its totient is φ = 694449600.

The previous prime is 2605638517. The next prime is 2605638551. The reversal of 2605638540 is 458365062.

It is a super-2 number, since 2×2605638540² = 13578704402266663200, which contains 22 as substring.

It is an unprimeable number.

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, 105931 + ... + 128189.

It is an arithmetic number, because the mean of its divisors is an integer number (152080320).

Almost surely, 2^2605638540 is an apocalyptic number.

2605638540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2605638540 is an abundant number, since it is smaller than the sum of its proper divisors (4694216820).

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

2605638540 is a wasteful number, since it uses less digits than its factorization.

2605638540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24222 (or 24220 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 39.

The square root of 2605638540 is about 51045.4556253542. The cubic root of 2605638540 is about 1376.0621725502.

The spelling of 2605638540 in words is "two billion, six hundred five million, six hundred thirty-eight thousand, five hundred forty".