40864640 has 64 divisors (see below), whose sum is σ = 99254160. Its totient is φ = 16084992.

The previous prime is 40864627. The next prime is 40864661. The reversal of 40864640 is 4646804.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 40864597 and 40864606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42404 + ... + 43356.

Almost surely, 2^40864640 is an apocalyptic number.

40864640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40864640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49627080).

40864640 is an abundant number, since it is smaller than the sum of its proper divisors (58389520).

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

40864640 is an equidigital number, since it uses as much as digits as its factorization.

40864640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1039 (or 1027 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 40864640 is about 6392.5456588123. The cubic root of 40864640 is about 344.4418335641.

The spelling of 40864640 in words is "forty million, eight hundred sixty-four thousand, six hundred forty".