181520914881 has 8 divisors (see below), whose sum is σ = 244424202624. Its totient is φ = 119815785200.

The previous prime is 181520914877. The next prime is 181520914921. The reversal of 181520914881 is 188419025181.

181520914881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 181520914881 - 2² = 181520914877 is a prime.

It is a super-2 number, since 2×181520914881² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 181520914881.

It is not an unprimeable number, because it can be changed into a prime (181520914481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 299539161 + ... + 299539766.

It is an arithmetic number, because the mean of its divisors is an integer number (30553025328).

Almost surely, 2^181520914881 is an apocalyptic number.

It is an amenable number.

181520914881 is a deficient number, since it is larger than the sum of its proper divisors (62903287743).

181520914881 is a wasteful number, since it uses less digits than its factorization.

181520914881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599079031.

The product of its (nonzero) digits is 184320, while the sum is 48.

The spelling of 181520914881 in words is "one hundred eighty-one billion, five hundred twenty million, nine hundred fourteen thousand, eight hundred eighty-one".