40205664 has 72 divisors (see below), whose sum is σ = 115282440. Its totient is φ = 13291008.

The previous prime is 40205657. The next prime is 40205701. The reversal of 40205664 is 46650204.

It is a happy number.

40205664 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38947 + ... + 39965.

It is an arithmetic number, because the mean of its divisors is an integer number (1601145).

Almost surely, 2^40205664 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 40205664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57641220).

40205664 is an abundant number, since it is smaller than the sum of its proper divisors (75076776).

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

40205664 is a wasteful number, since it uses less digits than its factorization.

40205664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1172 (or 1161 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 40205664 is about 6340.7936411777. The cubic root of 40205664 is about 342.5803217944.

Adding to 40205664 its reverse (46650204), we get a palindrome (86855868).

The spelling of 40205664 in words is "forty million, two hundred five thousand, six hundred sixty-four".