406181998656 has 840 divisors, whose sum is σ = 1469778067296. Its totient is φ = 110466478080.

The previous prime is 406181998619. The next prime is 406181998667. The reversal of 406181998656 is 656899181604.

406181998656 is a `hidden beast` number, since 4 + 0 + 618 + 1 + 9 + 9 + 8 + 6 + 5 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 406181998593 and 406181998602.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 447829755 + ... + 447830661.

Almost surely, 2^406181998656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 406181998656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (734889033648).

406181998656 is an abundant number, since it is smaller than the sum of its proper divisors (1063596068640).

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

406181998656 is a wasteful number, since it uses less digits than its factorization.

406181998656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1029 (or 1003 counting only the distinct ones).

The product of its (nonzero) digits is 22394880, while the sum is 63.

The spelling of 406181998656 in words is "four hundred six billion, one hundred eighty-one million, nine hundred ninety-eight thousand, six hundred fifty-six".