40309440 has 112 divisors (see below), whose sum is σ = 129235200. Its totient is φ = 10644480.

The previous prime is 40309439. The next prime is 40309453. The reversal of 40309440 is 4490304.

It is a super-2 number, since 2×40309440² = 3249701906227200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 40309440.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 190935 + ... + 191145.

Almost surely, 2^40309440 is an apocalyptic number.

40309440 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 40309440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64617600).

40309440 is an abundant number, since it is smaller than the sum of its proper divisors (88925760).

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

40309440 is a wasteful number, since it uses less digits than its factorization.

40309440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430 (or 420 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 40309440 is about 6348.9715702624. The cubic root of 40309440 is about 342.8748165493.

Adding to 40309440 its reverse (4490304), we get a palindrome (44799744).

The spelling of 40309440 in words is "forty million, three hundred nine thousand, four hundred forty".