38991131 has 2 divisors, whose sum is σ = 38991132. Its totient is φ = 38991130.

The previous prime is 38991103. The next prime is 38991133. The reversal of 38991131 is 13119983.

It is a strong prime.

It is an emirp because it is prime and its reverse (13119983) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-38991131 is a prime.

It is a super-2 number, since 2×38991131² = 3040616593318322, which contains 22 as substring.

Together with 38991133, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 38991091 and 38991100.

It is not a weakly prime, because it can be changed into another prime (38991133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19495565 + 19495566.

It is an arithmetic number, because the mean of its divisors is an integer number (19495566).

Almost surely, 2^38991131 is an apocalyptic number.

38991131 is a deficient number, since it is larger than the sum of its proper divisors (1).

38991131 is an equidigital number, since it uses as much as digits as its factorization.

38991131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832, while the sum is 35.

The square root of 38991131 is about 6244.2878697254. The cubic root of 38991131 is about 339.0954358104.

The spelling of 38991131 in words is "thirty-eight million, nine hundred ninety-one thousand, one hundred thirty-one".