20567409 has 8 divisors (see below), whose sum is σ = 28368960. Its totient is φ = 13238736.

The previous prime is 20567401. The next prime is 20567411. The reversal of 20567409 is 90476502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20567409 - 2³ = 20567401 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20567409.

It is not an unprimeable number, because it can be changed into a prime (20567401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118117 + ... + 118290.

It is an arithmetic number, because the mean of its divisors is an integer number (3546120).

Almost surely, 2^20567409 is an apocalyptic number.

20567409 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

20567409 is a deficient number, since it is larger than the sum of its proper divisors (7801551).

20567409 is a wasteful number, since it uses less digits than its factorization.

20567409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236439.

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 20567409 is about 4535.1305383638. The cubic root of 20567409 is about 273.9848367477.

The spelling of 20567409 in words is "twenty million, five hundred sixty-seven thousand, four hundred nine".