40645664 has 48 divisors (see below), whose sum is σ = 82938240. Its totient is φ = 19595520.

The previous prime is 40645663. The next prime is 40645711. The reversal of 40645664 is 46654604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40645663) 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, 149849 + ... + 150119.

It is an arithmetic number, because the mean of its divisors is an integer number (1727880).

Almost surely, 2^40645664 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 40645664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41469120).

40645664 is an abundant number, since it is smaller than the sum of its proper divisors (42292576).

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

40645664 is a wasteful number, since it uses less digits than its factorization.

40645664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 433 (or 425 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

The square root of 40645664 is about 6375.3952034364. The cubic root of 40645664 is about 343.8254928849.

The spelling of 40645664 in words is "forty million, six hundred forty-five thousand, six hundred sixty-four".