408991842181 has 8 divisors (see below), whose sum is σ = 441551144664. Its totient is φ = 376589452800.

The previous prime is 408991842109. The next prime is 408991842187. The reversal of 408991842181 is 181248199804.

It can be written as a sum of positive squares in 4 ways, for example, as 19573409025 + 389418433156 = 139905^2 + 624034^2 .

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 408991842181 - 2¹⁹ = 408991317893 is a prime.

It is a super-2 number, since 2×408991842181² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (408991842187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39222856 + ... + 39233281.

It is an arithmetic number, because the mean of its divisors is an integer number (55193893083).

Almost surely, 2^408991842181 is an apocalyptic number.

It is an amenable number.

408991842181 is a deficient number, since it is larger than the sum of its proper divisors (32559302483).

408991842181 is a wasteful number, since it uses less digits than its factorization.

408991842181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78456551.

The product of its (nonzero) digits is 1327104, while the sum is 55.

The spelling of 408991842181 in words is "four hundred eight billion, nine hundred ninety-one million, eight hundred forty-two thousand, one hundred eighty-one".