404380661 has 4 divisors (see below), whose sum is σ = 406956492. Its totient is φ = 401804832.

The previous prime is 404380657. The next prime is 404380673. The reversal of 404380661 is 166083404.

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 265494436 + 138886225 = 16294^2 + 11785^2 .

It is a cyclic number.

It is not a de Polignac number, because 404380661 - 2² = 404380657 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 (404380601) 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, 1287680 + ... + 1287993.

It is an arithmetic number, because the mean of its divisors is an integer number (101739123).

Almost surely, 2^404380661 is an apocalyptic number.

It is an amenable number.

404380661 is a deficient number, since it is larger than the sum of its proper divisors (2575831).

404380661 is a wasteful number, since it uses less digits than its factorization.

404380661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2575830.

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

The square root of 404380661 is about 20109.2183090243. The cubic root of 404380661 is about 739.4862888236.

The spelling of 404380661 in words is "four hundred four million, three hundred eighty thousand, six hundred sixty-one".