1638490275 has 120 divisors (see below), whose sum is σ = 3211096064. Its totient is φ = 824644800.

The previous prime is 1638490247. The next prime is 1638490297. The reversal of 1638490275 is 5720948361.

1638490275 is a `hidden beast` number, since 1 + 638 + 4 + 9 + 0 + 2 + 7 + 5 = 666.

1638490275 is digitally balanced in base 10, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1638490275 - 2¹¹ = 1638488227 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

1638490275 is strictly pandigital in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 1638490275.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 2699022 + ... + 2699628.

It is a 1-persistent number, because it is pandigital, but 2⋅1638490275 = 3276980550 is not.

Almost surely, 2^1638490275 is an apocalyptic number.

1638490275 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1638490275 is a deficient number, since it is larger than the sum of its proper divisors (1572605789).

1638490275 is a wasteful number, since it uses less digits than its factorization.

1638490275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 703 (or 689 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 1638490275 is about 40478.2691700127. The cubic root of 1638490275 is about 1178.9117312469.

The spelling of 1638490275 in words is "one billion, six hundred thirty-eight million, four hundred ninety thousand, two hundred seventy-five".