40218869 has 2 divisors, whose sum is σ = 40218870. Its totient is φ = 40218868.

The previous prime is 40218859. The next prime is 40218883. The reversal of 40218869 is 96881204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38626225 + 1592644 = 6215^2 + 1262^2 .

It is a cyclic number.

It is not a de Polignac number, because 40218869 - 2⁸ = 40218613 is a prime.

It is a super-2 number, since 2×40218869² = 3235114847278322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40218809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20109434 + 20109435.

It is an arithmetic number, because the mean of its divisors is an integer number (20109435).

Almost surely, 2^40218869 is an apocalyptic number.

It is an amenable number.

40218869 is a deficient number, since it is larger than the sum of its proper divisors (1).

40218869 is an equidigital number, since it uses as much as digits as its factorization.

40218869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 40218869 is about 6341.8348291327. The cubic root of 40218869 is about 342.6178229616.

The spelling of 40218869 in words is "forty million, two hundred eighteen thousand, eight hundred sixty-nine".