20423665 has 8 divisors (see below), whose sum is σ = 24572520. Its totient is φ = 16296192.

The previous prime is 20423653. The next prime is 20423707. The reversal of 20423665 is 56632402.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 7144929 + 13278736 = 2673^2 + 3644^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20423665 - 2²¹ = 18326513 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3160 + ... + 7129.

It is an arithmetic number, because the mean of its divisors is an integer number (3071565).

Almost surely, 2^20423665 is an apocalyptic number.

It is an amenable number.

20423665 is a deficient number, since it is larger than the sum of its proper divisors (4148855).

20423665 is a wasteful number, since it uses less digits than its factorization.

20423665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10691.

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 20423665 is about 4519.2549164658. The cubic root of 20423665 is about 273.3450578288.

The spelling of 20423665 in words is "twenty million, four hundred twenty-three thousand, six hundred sixty-five".