38690891 has 4 divisors (see below), whose sum is σ = 38760912. Its totient is φ = 38620872.

The previous prime is 38690887. The next prime is 38690909. The reversal of 38690891 is 19809683.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19809683 = 41 ⋅483163.

It is a cyclic number.

It is not a de Polignac number, because 38690891 - 2² = 38690887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38690831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34175 + ... + 35288.

It is an arithmetic number, because the mean of its divisors is an integer number (9690228).

Almost surely, 2^38690891 is an apocalyptic number.

38690891 is a deficient number, since it is larger than the sum of its proper divisors (70021).

38690891 is an equidigital number, since it uses as much as digits as its factorization.

38690891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70020.

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 38690891 is about 6220.2002379345. The cubic root of 38690891 is about 338.2228232078. Note that the first 3 decimals are identical.

The spelling of 38690891 in words is "thirty-eight million, six hundred ninety thousand, eight hundred ninety-one".