38991031 has 2 divisors, whose sum is σ = 38991032. Its totient is φ = 38991030.

The previous prime is 38991019. The next prime is 38991037. The reversal of 38991031 is 13019983.

It is a strong prime.

It is an emirp because it is prime and its reverse (13019983) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 38991031 - 2⁹ = 38990519 is a prime.

It is a super-2 number, since 2×38991031² = 3040600996885922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38991037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19495515 + 19495516.

It is an arithmetic number, because the mean of its divisors is an integer number (19495516).

Almost surely, 2^38991031 is an apocalyptic number.

38991031 is a deficient number, since it is larger than the sum of its proper divisors (1).

38991031 is an equidigital number, since it uses as much as digits as its factorization.

38991031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 38991031 is about 6244.2798624021. The cubic root of 38991031 is about 339.0951459191.

The spelling of 38991031 in words is "thirty-eight million, nine hundred ninety-one thousand, thirty-one".