40345640 has 64 divisors (see below), whose sum is σ = 94545360. Its totient is φ = 15482880.

The previous prime is 40345637. The next prime is 40345649. The reversal of 40345640 is 4654304.

It can be written as a sum of positive squares in 8 ways, for example, as 4656964 + 35688676 = 2158^2 + 5974^2 .

It is not an unprimeable number, because it can be changed into a prime (40345649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119552 + ... + 119888.

Almost surely, 2^40345640 is an apocalyptic number.

40345640 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 40345640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47272680).

40345640 is an abundant number, since it is smaller than the sum of its proper divisors (54199720).

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

40345640 is a wasteful number, since it uses less digits than its factorization.

40345640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462 (or 458 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 26.

The square root of 40345640 is about 6351.8217859131. The cubic root of 40345640 is about 342.9774257201.

Adding to 40345640 its reverse (4654304), we get a palindrome (44999944).

The spelling of 40345640 in words is "forty million, three hundred forty-five thousand, six hundred forty".