40218169 has 4 divisors (see below), whose sum is σ = 40574196. Its totient is φ = 39862144.

The previous prime is 40218151. The next prime is 40218181. The reversal of 40218169 is 96181204.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5702544 + 34515625 = 2388^2 + 5875^2 .

It is a cyclic number.

It is not a de Polignac number, because 40218169 - 2⁵ = 40218137 is a prime.

It is a super-2 number, since 2×40218169² = 3235002235425122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 40218169.

It is not an unprimeable number, because it can be changed into a prime (40218119) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177844 + ... + 178069.

It is an arithmetic number, because the mean of its divisors is an integer number (10143549).

Almost surely, 2^40218169 is an apocalyptic number.

It is an amenable number.

40218169 is a deficient number, since it is larger than the sum of its proper divisors (356027).

40218169 is a wasteful number, since it uses less digits than its factorization.

40218169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356026.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 40218169 is about 6341.7796398172. The cubic root of 40218169 is about 342.6158352224.

The spelling of 40218169 in words is "forty million, two hundred eighteen thousand, one hundred sixty-nine".