20406653 has 4 divisors (see below), whose sum is σ = 20593980. Its totient is φ = 20219328.

The previous prime is 20406641. The next prime is 20406667. The reversal of 20406653 is 35660402.

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 14462809 + 5943844 = 3803^2 + 2438^2 .

It is a cyclic number.

It is not a de Polignac number, because 20406653 - 2¹⁴ = 20390269 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20466653) 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, 93500 + ... + 93717.

It is an arithmetic number, because the mean of its divisors is an integer number (5148495).

Almost surely, 2^20406653 is an apocalyptic number.

It is an amenable number.

20406653 is a deficient number, since it is larger than the sum of its proper divisors (187327).

20406653 is a wasteful number, since it uses less digits than its factorization.

20406653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187326.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 20406653 is about 4517.3723556953. The cubic root of 20406653 is about 273.2691420085.

The spelling of 20406653 in words is "twenty million, four hundred six thousand, six hundred fifty-three".