21160409 has 16 divisors (see below), whose sum is σ = 22472640. Its totient is φ = 19905600.

The previous prime is 21160397. The next prime is 21160439. The reversal of 21160409 is 90406112.

21160409 = T₁₀₂ + T₁₀₃ + ... + T₅₀₃.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21160409 - 2¹⁶ = 21094873 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21160439) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209459 + ... + 209559.

It is an arithmetic number, because the mean of its divisors is an integer number (1404540).

Almost surely, 2^21160409 is an apocalyptic number.

It is an amenable number.

21160409 is a deficient number, since it is larger than the sum of its proper divisors (1312231).

21160409 is a wasteful number, since it uses less digits than its factorization.

21160409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 21160409 is about 4600.0444563069. The cubic root of 21160409 is about 276.5931068449.

The spelling of 21160409 in words is "twenty-one million, one hundred sixty thousand, four hundred nine".