409112021 has 4 divisors (see below), whose sum is σ = 433177452. Its totient is φ = 385046592.

The previous prime is 409111979. The next prime is 409112023. The reversal of 409112021 is 120211904.

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 291931396 + 117180625 = 17086^2 + 10825^2 .

It is a cyclic number.

It is not a de Polignac number, because 409112021 - 2²² = 404917717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 409111984 and 409112002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (409112023) 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, 12032690 + ... + 12032723.

It is an arithmetic number, because the mean of its divisors is an integer number (108294363).

Almost surely, 2^409112021 is an apocalyptic number.

It is an amenable number.

409112021 is a deficient number, since it is larger than the sum of its proper divisors (24065431).

409112021 is a wasteful number, since it uses less digits than its factorization.

409112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24065430.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 409112021 is about 20226.5177675249. The cubic root of 409112021 is about 742.3591745831.

Adding to 409112021 its reverse (120211904), we get a palindrome (529323925).

The spelling of 409112021 in words is "four hundred nine million, one hundred twelve thousand, twenty-one".