81958143381 has 8 divisors (see below), whose sum is σ = 111068959584. Its totient is φ = 53743044720.

The previous prime is 81958143349. The next prime is 81958143383. The reversal of 81958143381 is 18334185918.

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

It is not a de Polignac number, because 81958143381 - 2⁵ = 81958143349 is a prime.

It is a super-2 number, since 2×81958143381² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81958143383) 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, 223929171 + ... + 223929536.

It is an arithmetic number, because the mean of its divisors is an integer number (13883619948).

Almost surely, 2^81958143381 is an apocalyptic number.

It is an amenable number.

81958143381 is a deficient number, since it is larger than the sum of its proper divisors (29110816203).

81958143381 is a wasteful number, since it uses less digits than its factorization.

81958143381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447858771.

The product of its digits is 829440, while the sum is 51.

The spelling of 81958143381 in words is "eighty-one billion, nine hundred fifty-eight million, one hundred forty-three thousand, three hundred eighty-one".