181397666016 has 432 divisors, whose sum is σ = 614268358704. Its totient is φ = 50611212288.

The previous prime is 181397665979. The next prime is 181397666041. The reversal of 181397666016 is 610666793181.

It is a super-2 number, since 2×181397666016² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 211665460 + ... + 211666316.

It is an arithmetic number, because the mean of its divisors is an integer number (1421917497).

Almost surely, 2^181397666016 is an apocalyptic number.

181397666016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181397666016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (307134179352).

181397666016 is an abundant number, since it is smaller than the sum of its proper divisors (432870692688).

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

181397666016 is a wasteful number, since it uses less digits than its factorization.

181397666016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1223 (or 1205 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 54.

The spelling of 181397666016 in words is "one hundred eighty-one billion, three hundred ninety-seven million, six hundred sixty-six thousand, sixteen".