8131891901 has 8 divisors (see below), whose sum is σ = 9297003264. Its totient is φ = 6967633680.

The previous prime is 8131891897. The next prime is 8131891927. The reversal of 8131891901 is 1091981318.

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

It is not a de Polignac number, because 8131891901 - 2² = 8131891897 is a prime.

It is a super-2 number, since 2×8131891901² (a number of 21 digits) 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 (8131891961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 192725 + ... + 231098.

It is an arithmetic number, because the mean of its divisors is an integer number (1162125408).

Almost surely, 2^8131891901 is an apocalyptic number.

It is an amenable number.

8131891901 is a deficient number, since it is larger than the sum of its proper divisors (1165111363).

8131891901 is a wasteful number, since it uses less digits than its factorization.

8131891901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426571.

The product of its (nonzero) digits is 15552, while the sum is 41.

The square root of 8131891901 is about 90177.0031715404. The cubic root of 8131891901 is about 2010.9311380143.

The spelling of 8131891901 in words is "eight billion, one hundred thirty-one million, eight hundred ninety-one thousand, nine hundred one".