43215440 has 40 divisors (see below), whose sum is σ = 101529960. Its totient is φ = 17104896.

The previous prime is 43215427. The next prime is 43215461. The reversal of 43215440 is 4451234.

It can be written as a sum of positive squares in 4 ways, for example, as 652864 + 42562576 = 808^2 + 6524^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4976 + ... + 10544.

It is an arithmetic number, because the mean of its divisors is an integer number (2538249).

Almost surely, 2^43215440 is an apocalyptic number.

43215440 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 43215440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50764980).

43215440 is an abundant number, since it is smaller than the sum of its proper divisors (58314520).

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

43215440 is a wasteful number, since it uses less digits than its factorization.

43215440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5679 (or 5673 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 43215440 is about 6573.8451457271. The cubic root of 43215440 is about 350.9239262303.

Adding to 43215440 its reverse (4451234), we get a palindrome (47666674).

The spelling of 43215440 in words is "forty-three million, two hundred fifteen thousand, four hundred forty".