2188638460 has 24 divisors (see below), whose sum is σ = 4597898256. Its totient is φ = 875120640.

The previous prime is 2188638457. The next prime is 2188638461. The reversal of 2188638460 is 648368812.

It is a self number, because there is not a number n which added to its sum of digits gives 2188638460.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2188638461) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36540 + ... + 75580.

It is an arithmetic number, because the mean of its divisors is an integer number (191579094).

Almost surely, 2^2188638460 is an apocalyptic number.

2188638460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2188638460 is an abundant number, since it is smaller than the sum of its proper divisors (2409259796).

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

2188638460 is a wasteful number, since it uses less digits than its factorization.

2188638460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41853 (or 41851 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 46.

The square root of 2188638460 is about 46782.8864009052. The cubic root of 2188638460 is about 1298.3486843815.

The spelling of 2188638460 in words is "two billion, one hundred eighty-eight million, six hundred thirty-eight thousand, four hundred sixty".