40405521 has 8 divisors (see below), whose sum is σ = 58018240. Its totient is φ = 24864912.

The previous prime is 40405471. The next prime is 40405529. The reversal of 40405521 is 12550404.

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

It is not a de Polignac number, because 40405521 - 2⁹ = 40405009 is a prime.

It is a super-2 number, since 2×40405521² = 3265212254562882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (40405529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 517981 + ... + 518058.

It is an arithmetic number, because the mean of its divisors is an integer number (7252280).

Almost surely, 2^40405521 is an apocalyptic number.

It is an amenable number.

40405521 is a deficient number, since it is larger than the sum of its proper divisors (17612719).

40405521 is a wasteful number, since it uses less digits than its factorization.

40405521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1036055.

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 40405521 is about 6356.5337252311. The cubic root of 40405521 is about 343.1470242100.

Adding to 40405521 its reverse (12550404), we get a palindrome (52955925).

The spelling of 40405521 in words is "forty million, four hundred five thousand, five hundred twenty-one".