181045447990531 has 4 divisors (see below), whose sum is σ = 181054933284832. Its totient is φ = 181035962696232.

The previous prime is 181045447990457. The next prime is 181045447990591. The reversal of 181045447990531 is 135099744540181.

181045447990531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 181045447990531 - 2³¹ = 181043300506883 is a prime.

It is a super-2 number, since 2×181045447990531² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 181045447990531.

It is not an unprimeable number, because it can be changed into a prime (181045447990591) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4742618520 + ... + 4742656693.

It is an arithmetic number, because the mean of its divisors is an integer number (45263733321208).

Almost surely, 2^{181045447990531} is an apocalyptic number.

181045447990531 is a deficient number, since it is larger than the sum of its proper divisors (9485294301).

181045447990531 is an equidigital number, since it uses as much as digits as its factorization.

181045447990531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9485294300.

The product of its (nonzero) digits is 21772800, while the sum is 61.

The spelling of 181045447990531 in words is "one hundred eighty-one trillion, forty-five billion, four hundred forty-seven million, nine hundred ninety thousand, five hundred thirty-one".