20971259506 has 4 divisors (see below), whose sum is σ = 31456889262. Its totient is φ = 10485629752.

The previous prime is 20971259503. The next prime is 20971259509. The reversal of 20971259506 is 60595217902.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20971259503) and next prime (20971259509).

It can be written as a sum of positive squares in only one way, i.e., 20048011281 + 923248225 = 141591^2 + 30385^2 .

It is not an unprimeable number, because it can be changed into a prime (20971259501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5242814875 + ... + 5242814878.

Almost surely, 2^20971259506 is an apocalyptic number.

20971259506 is a deficient number, since it is larger than the sum of its proper divisors (10485629756).

20971259506 is a wasteful number, since it uses less digits than its factorization.

20971259506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10485629755.

The product of its (nonzero) digits is 340200, while the sum is 46.

The spelling of 20971259506 in words is "twenty billion, nine hundred seventy-one million, two hundred fifty-nine thousand, five hundred six".