1638203648 has 36 divisors (see below), whose sum is σ = 3273016320. Its totient is φ = 818348544.

The previous prime is 1638203647. The next prime is 1638203717. The reversal of 1638203648 is 8463028361.

It is a happy number.

It is a super-2 number, since 2×1638203648² = 5367422384641015808, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1638203641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 366161 + ... + 370607.

It is an arithmetic number, because the mean of its divisors is an integer number (90917120).

Almost surely, 2^1638203648 is an apocalyptic number.

It is an amenable number.

1638203648 is a deficient number, since it is larger than the sum of its proper divisors (1634812672).

1638203648 is an equidigital number, since it uses as much as digits as its factorization.

1638203648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5902 (or 5888 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 41.

The square root of 1638203648 is about 40474.7285105163. The cubic root of 1638203648 is about 1178.8429834808.

The spelling of 1638203648 in words is "one billion, six hundred thirty-eight million, two hundred three thousand, six hundred forty-eight".