38990991816 has 256 divisors, whose sum is σ = 130749696000. Its totient is φ = 10517195520.

The previous prime is 38990991803. The next prime is 38990991817. The reversal of 38990991816 is 61819909983.

38990991816 is a `hidden beast` number, since 389 + 90 + 9 + 91 + 81 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (38990991817) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 8817286 + ... + 8821706.

It is an arithmetic number, because the mean of its divisors is an integer number (510741000).

Almost surely, 2^38990991816 is an apocalyptic number.

38990991816 is a gapful number since it is divisible by the number (36) 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 38990991816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65374848000).

38990991816 is an abundant number, since it is smaller than the sum of its proper divisors (91758704184).

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

38990991816 is a wasteful number, since it uses less digits than its factorization.

38990991816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4769 (or 4759 counting only the distinct ones).

The product of its (nonzero) digits is 7558272, while the sum is 63.

The spelling of 38990991816 in words is "thirty-eight billion, nine hundred ninety million, nine hundred ninety-one thousand, eight hundred sixteen".