20646131 has 8 divisors (see below), whose sum is σ = 22777200. Its totient is φ = 18557440.

The previous prime is 20646107. The next prime is 20646137. The reversal of 20646131 is 13164602.

It is a happy number.

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

It is not a de Polignac number, because 20646131 - 2¹⁴ = 20629747 is a prime.

It is a super-2 number, since 2×20646131² = 852525450538322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20646097 and 20646106.

It is not an unprimeable number, because it can be changed into a prime (20646137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9566 + ... + 11523.

It is an arithmetic number, because the mean of its divisors is an integer number (2847150).

Almost surely, 2^20646131 is an apocalyptic number.

20646131 is a deficient number, since it is larger than the sum of its proper divisors (2131069).

20646131 is a wasteful number, since it uses less digits than its factorization.

20646131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21189.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 20646131 is about 4543.8013821029. The cubic root of 20646131 is about 274.3339517742. Note that the first 3 decimals are identical.

The spelling of 20646131 in words is "twenty million, six hundred forty-six thousand, one hundred thirty-one".