81244354242 has 16 divisors (see below), whose sum is σ = 162865717632. Its totient is φ = 27018616560.

The previous prime is 81244354229. The next prime is 81244354249. The reversal of 81244354242 is 24245344218.

It is a self number, because there is not a number n which added to its sum of digits gives 81244354242.

It is not an unprimeable number, because it can be changed into a prime (81244354249) 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, 15705913 + ... + 15711084.

It is an arithmetic number, because the mean of its divisors is an integer number (10179107352).

Almost surely, 2^81244354242 is an apocalyptic number.

81244354242 is an abundant number, since it is smaller than the sum of its proper divisors (81621363390).

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

81244354242 is a wasteful number, since it uses less digits than its factorization.

81244354242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31417433.

The product of its digits is 245760, while the sum is 39.

The spelling of 81244354242 in words is "eighty-one billion, two hundred forty-four million, three hundred fifty-four thousand, two hundred forty-two".