38821978581 has 4 divisors (see below), whose sum is σ = 51762638112. Its totient is φ = 25881319052.

The previous prime is 38821978579. The next prime is 38821978597. The reversal of 38821978581 is 18587912883.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 38821978581 - 2¹ = 38821978579 is a prime.

It is a super-2 number, since 2×38821978581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (38821978501) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 6470329761 + ... + 6470329766.

It is an arithmetic number, because the mean of its divisors is an integer number (12940659528).

Almost surely, 2^38821978581 is an apocalyptic number.

It is an amenable number.

38821978581 is a deficient number, since it is larger than the sum of its proper divisors (12940659531).

38821978581 is a wasteful number, since it uses less digits than its factorization.

38821978581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12940659530.

The product of its digits is 7741440, while the sum is 60.

The spelling of 38821978581 in words is "thirty-eight billion, eight hundred twenty-one million, nine hundred seventy-eight thousand, five hundred eighty-one".