40691521 has 8 divisors (see below), whose sum is σ = 46128320. Its totient is φ = 35584272.

The previous prime is 40691509. The next prime is 40691543. The reversal of 40691521 is 12519604.

40691521 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 40691521 - 2¹⁷ = 40560449 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 40691521.

It is not an unprimeable number, because it can be changed into a prime (40691501) 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, 82125 + ... + 82618.

It is an arithmetic number, because the mean of its divisors is an integer number (5766040).

Almost surely, 2^40691521 is an apocalyptic number.

It is an amenable number.

40691521 is a deficient number, since it is larger than the sum of its proper divisors (5436799).

40691521 is a wasteful number, since it uses less digits than its factorization.

40691521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164775.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 40691521 is about 6378.9905941301. The cubic root of 40691521 is about 343.9547471796.

The spelling of 40691521 in words is "forty million, six hundred ninety-one thousand, five hundred twenty-one".