40404213 has 6 divisors (see below), whose sum is σ = 58361654. Its totient is φ = 26936136.

The previous prime is 40404209. The next prime is 40404233. The reversal of 40404213 is 31240404.

It can be written as a sum of positive squares in only one way, i.e., 25979409 + 14424804 = 5097^2 + 3798^2 .

It is not a de Polignac number, because 40404213 - 2² = 40404209 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40404233) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2244670 + ... + 2244687.

Almost surely, 2^40404213 is an apocalyptic number.

It is an amenable number.

40404213 is a deficient number, since it is larger than the sum of its proper divisors (17957441).

40404213 is a wasteful number, since it uses less digits than its factorization.

40404213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4489363 (or 4489360 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 40404213 is about 6356.4308381355. The cubic root of 40404213 is about 343.1433214062.

Adding to 40404213 its reverse (31240404), we get a palindrome (71644617).

The spelling of 40404213 in words is "forty million, four hundred four thousand, two hundred thirteen".