181297981436 has 48 divisors (see below), whose sum is σ = 388944557568. Its totient is φ = 72761726400.

The previous prime is 181297981427. The next prime is 181297981463. The reversal of 181297981436 is 634189792181.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6877160 + ... + 6903471.

It is an arithmetic number, because the mean of its divisors is an integer number (8103011616).

Almost surely, 2^181297981436 is an apocalyptic number.

It is an amenable number.

181297981436 is an abundant number, since it is smaller than the sum of its proper divisors (207646576132).

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

181297981436 is a wasteful number, since it uses less digits than its factorization.

181297981436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13780682 (or 13780680 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 59.

The spelling of 181297981436 in words is "one hundred eighty-one billion, two hundred ninety-seven million, nine hundred eighty-one thousand, four hundred thirty-six".