406905381540 has 324 divisors, whose sum is σ = 1449014239764. Its totient is φ = 92158359552.

The previous prime is 406905381469. The next prime is 406905381569. The reversal of 406905381540 is 45183509604.

406905381540 is a `hidden beast` number, since 4 + 0 + 69 + 0 + 538 + 1 + 54 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 324544417344 + 82360964196 = 569688^2 + 286986^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 112620774 + ... + 112624386.

Almost surely, 2^406905381540 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 406905381540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (724507119882).

406905381540 is an abundant number, since it is smaller than the sum of its proper divisors (1042108858224).

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

406905381540 is a wasteful number, since it uses less digits than its factorization.

406905381540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3868 (or 3743 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 406905381540 in words is "four hundred six billion, nine hundred five million, three hundred eighty-one thousand, five hundred forty".