20646243267 has 16 divisors (see below), whose sum is σ = 30668161440. Its totient is φ = 12267263232.

The previous prime is 20646243253. The next prime is 20646243271. The reversal of 20646243267 is 76234264602.

It is not a de Polignac number, because 20646243267 - 2⁶ = 20646243203 is a prime.

It is a super-2 number, since 2×20646243267² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20646243217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9126298 + ... + 9128559.

It is an arithmetic number, because the mean of its divisors is an integer number (1916760090).

Almost surely, 2^20646243267 is an apocalyptic number.

20646243267 is a deficient number, since it is larger than the sum of its proper divisors (10021918173).

20646243267 is a wasteful number, since it uses less digits than its factorization.

20646243267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18254902.

The product of its (nonzero) digits is 580608, while the sum is 42.

The spelling of 20646243267 in words is "twenty billion, six hundred forty-six million, two hundred forty-three thousand, two hundred sixty-seven".