38871981 has 24 divisors (see below), whose sum is σ = 58522464. Its totient is φ = 25783920.

The previous prime is 38871947. The next prime is 38871983. The reversal of 38871981 is 18917883.

38871981 = T₁₅₈ + T₁₅₉ + ... + T₆₁₈.

It is not a de Polignac number, because 38871981 - 2¹¹ = 38869933 is a prime.

It is a super-2 number, since 2×38871981² = 3022061813728722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (38871983) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 84091 + ... + 84551.

It is an arithmetic number, because the mean of its divisors is an integer number (2438436).

Almost surely, 2^38871981 is an apocalyptic number.

It is an amenable number.

38871981 is a deficient number, since it is larger than the sum of its proper divisors (19650483).

38871981 is an equidigital number, since it uses as much as digits as its factorization.

38871981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823 (or 811 counting only the distinct ones).

The product of its digits is 96768, while the sum is 45.

The square root of 38871981 is about 6234.7398502263. The cubic root of 38871981 is about 338.7496781540.

The spelling of 38871981 in words is "thirty-eight million, eight hundred seventy-one thousand, nine hundred eighty-one".