38215891 has 4 divisors (see below), whose sum is σ = 43675312. Its totient is φ = 32756472.

The previous prime is 38215883. The next prime is 38215927. The reversal of 38215891 is 19851283.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19851283 = 29 ⋅684527.

It is not a de Polignac number, because 38215891 - 2³ = 38215883 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 38215891.

It is not an unprimeable number, because it can be changed into a prime (38215831) 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, 2729700 + ... + 2729713.

It is an arithmetic number, because the mean of its divisors is an integer number (10918828).

Almost surely, 2^38215891 is an apocalyptic number.

38215891 is a deficient number, since it is larger than the sum of its proper divisors (5459421).

38215891 is an equidigital number, since it uses as much as digits as its factorization.

38215891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5459420.

The product of its digits is 17280, while the sum is 37.

The square root of 38215891 is about 6181.9002741875. The cubic root of 38215891 is about 336.8330231451.

The spelling of 38215891 in words is "thirty-eight million, two hundred fifteen thousand, eight hundred ninety-one".