201638481408 has 1200 divisors, whose sum is σ = 781995636576. Its totient is φ = 50363596800.

The previous prime is 201638481347. The next prime is 201638481437. The reversal of 201638481408 is 804184836102.

201638481408 is a `hidden beast` number, since 2 + 0 + 1 + 638 + 4 + 8 + 1 + 4 + 0 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1996420558 + ... + 1996420658.

Almost surely, 2^201638481408 is an apocalyptic number.

201638481408 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 201638481408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (390997818288).

201638481408 is an abundant number, since it is smaller than the sum of its proper divisors (580357155168).

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

201638481408 is a wasteful number, since it uses less digits than its factorization.

201638481408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197 (or 149 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 45.

The spelling of 201638481408 in words is "two hundred one billion, six hundred thirty-eight million, four hundred eighty-one thousand, four hundred eight".