81947930202 has 40 divisors (see below), whose sum is σ = 193288497600. Its totient is φ = 25878292776.

The previous prime is 81947930179. The next prime is 81947930203. The reversal of 81947930202 is 20203974918.

It is not an unprimeable number, because it can be changed into a prime (81947930203) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 13308802 + ... + 13314957.

It is an arithmetic number, because the mean of its divisors is an integer number (4832212440).

Almost surely, 2^81947930202 is an apocalyptic number.

81947930202 is an abundant number, since it is smaller than the sum of its proper divisors (111340567398).

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

81947930202 is a wasteful number, since it uses less digits than its factorization.

81947930202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26623792 (or 26623783 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 81947930202 in words is "eighty-one billion, nine hundred forty-seven million, nine hundred thirty thousand, two hundred two".