8191381 has 8 divisors (see below), whose sum is σ = 9324864. Its totient is φ = 7122720.

The previous prime is 8191363. The next prime is 8191387. The reversal of 8191381 is 1831918.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 8191381 - 2¹¹ = 8189333 is a prime.

It is a super-2 number, since 2×8191381² = 134197445374322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8191387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15936 + ... + 16441.

It is an arithmetic number, because the mean of its divisors is an integer number (1165608).

Almost surely, 2^8191381 is an apocalyptic number.

It is an amenable number.

8191381 is a deficient number, since it is larger than the sum of its proper divisors (1133483).

8191381 is a wasteful number, since it uses less digits than its factorization.

8191381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32411.

The product of its digits is 1728, while the sum is 31.

The square root of 8191381 is about 2862.0588743071. The cubic root of 8191381 is about 201.5822904391.

The spelling of 8191381 in words is "eight million, one hundred ninety-one thousand, three hundred eighty-one".