40215521 has 8 divisors (see below), whose sum is σ = 41324640. Its totient is φ = 39120768.

The previous prime is 40215479. The next prime is 40215529. The reversal of 40215521 is 12551204.

40215521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 40215521 - 2¹⁰ = 40214497 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40215493 and 40215502.

It is not an unprimeable number, because it can be changed into a prime (40215529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2210 + ... + 9236.

It is an arithmetic number, because the mean of its divisors is an integer number (5165580).

Almost surely, 2^40215521 is an apocalyptic number.

It is an amenable number.

40215521 is a deficient number, since it is larger than the sum of its proper divisors (1109119).

40215521 is an equidigital number, since it uses as much as digits as its factorization.

40215521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7183.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 40215521 is about 6341.5708621760. The cubic root of 40215521 is about 342.6083156803.

Adding to 40215521 its reverse (12551204), we get a palindrome (52766725).

The spelling of 40215521 in words is "forty million, two hundred fifteen thousand, five hundred twenty-one".