1638413620 has 24 divisors (see below), whose sum is σ = 3461278464. Its totient is φ = 651439776.

The previous prime is 1638413599. The next prime is 1638413653. The reversal of 1638413620 is 263148361.

It is a happy number.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 241932 + ... + 248611.

It is an arithmetic number, because the mean of its divisors is an integer number (144219936).

Almost surely, 2^1638413620 is an apocalyptic number.

1638413620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1638413620 is an abundant number, since it is smaller than the sum of its proper divisors (1822864844).

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

1638413620 is a wasteful number, since it uses less digits than its factorization.

1638413620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490719 (or 490717 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 1638413620 is about 40477.3222928592. The cubic root of 1638413620 is about 1178.8933462557.

The spelling of 1638413620 in words is "one billion, six hundred thirty-eight million, four hundred thirteen thousand, six hundred twenty".