40404389 has 2 divisors, whose sum is σ = 40404390. Its totient is φ = 40404388.

The previous prime is 40404383. The next prime is 40404409. The reversal of 40404389 is 98340404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39816100 + 588289 = 6310^2 + 767^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40404389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40404383) 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 as a sum of consecutive naturals, namely, 20202194 + 20202195.

It is an arithmetic number, because the mean of its divisors is an integer number (20202195).

Almost surely, 2^40404389 is an apocalyptic number.

It is an amenable number.

40404389 is a deficient number, since it is larger than the sum of its proper divisors (1).

40404389 is an equidigital number, since it uses as much as digits as its factorization.

40404389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 40404389 is about 6356.4446823677. Note that the first 3 decimals coincide. The cubic root of 40404389 is about 343.1438196474.

The spelling of 40404389 in words is "forty million, four hundred four thousand, three hundred eighty-nine".