40213521 has 12 divisors (see below), whose sum is σ = 58266000. Its totient is φ = 26726040.

The previous prime is 40213513. The next prime is 40213531. The reversal of 40213521 is 12531204.

It is not a de Polignac number, because 40213521 - 2³ = 40213513 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 40213494 and 40213503.

It is not an unprimeable number, because it can be changed into a prime (40213531) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 3771 + ... + 9728.

It is an arithmetic number, because the mean of its divisors is an integer number (4855500).

Almost surely, 2^40213521 is an apocalyptic number.

It is an amenable number.

40213521 is a deficient number, since it is larger than the sum of its proper divisors (18052479).

40213521 is a wasteful number, since it uses less digits than its factorization.

40213521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13836 (or 13833 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 40213521 is about 6341.4131705796. The cubic root of 40213521 is about 342.6026360490.

Adding to 40213521 its reverse (12531204), we get a palindrome (52744725).

The spelling of 40213521 in words is "forty million, two hundred thirteen thousand, five hundred twenty-one".