81142253222142 has 128 divisors (see below), whose sum is σ = 192423231959040. Its totient is φ = 22318786344960.

The previous prime is 81142253222137. The next prime is 81142253222207. The reversal of 81142253222142 is 24122235224118.

It is a self number, because there is not a number n which added to its sum of digits gives 81142253222142.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2843390898 + ... + 2843419434.

It is an arithmetic number, because the mean of its divisors is an integer number (1503306499680).

Almost surely, 2^{81142253222142} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81142253222142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96211615979520).

81142253222142 is an abundant number, since it is smaller than the sum of its proper divisors (111280978736898).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81142253222142 is a wasteful number, since it uses less digits than its factorization.

81142253222142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35306.

The product of its digits is 122880, while the sum is 39.

The spelling of 81142253222142 in words is "eighty-one trillion, one hundred forty-two billion, two hundred fifty-three million, two hundred twenty-two thousand, one hundred forty-two".