1638271488 has 120 divisors (see below), whose sum is σ = 5077255392. Its totient is φ = 468056064.

The previous prime is 1638271483. The next prime is 1638271493. The reversal of 1638271488 is 8841728361.

It is an interprime number because it is at equal distance from previous prime (1638271483) and next prime (1638271493).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638271483) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64381 + ... + 86147.

Almost surely, 2^1638271488 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1638271488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2538627696).

1638271488 is an abundant number, since it is smaller than the sum of its proper divisors (3438983904).

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

1638271488 is an equidigital number, since it uses as much as digits as its factorization.

1638271488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21802 (or 21779 counting only the distinct ones).

The product of its digits is 516096, while the sum is 48.

The square root of 1638271488 is about 40475.5665556395. The cubic root of 1638271488 is about 1178.8592556955.

The spelling of 1638271488 in words is "one billion, six hundred thirty-eight million, two hundred seventy-one thousand, four hundred eighty-eight".