40405668 has 72 divisors (see below), whose sum is σ = 102326784. Its totient is φ = 12403200.

The previous prime is 40405657. The next prime is 40405669. The reversal of 40405668 is 86650404.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (40405669) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 211453 + ... + 211643.

Almost surely, 2^40405668 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 40405668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51163392).

40405668 is an abundant number, since it is smaller than the sum of its proper divisors (61921116).

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

40405668 is a wasteful number, since it uses less digits than its factorization.

40405668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293 (or 274 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The square root of 40405668 is about 6356.5452881262. The cubic root of 40405668 is about 343.1474403458.

The spelling of 40405668 in words is "forty million, four hundred five thousand, six hundred sixty-eight".