20971603634 has 8 divisors (see below), whose sum is σ = 32542143660. Its totient is φ = 10124222416.

The previous prime is 20971603621. The next prime is 20971603637. The reversal of 20971603634 is 43630617902.

It can be written as a sum of positive squares in 2 ways, for example, as 20850493609 + 121110025 = 144397^2 + 11005^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 20971603591 and 20971603600.

It is not an unprimeable number, because it can be changed into a prime (20971603637) 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 3 ways as a sum of consecutive naturals, for example, 180789629 + ... + 180789744.

Almost surely, 2^20971603634 is an apocalyptic number.

20971603634 is a deficient number, since it is larger than the sum of its proper divisors (11570540026).

20971603634 is a wasteful number, since it uses less digits than its factorization.

20971603634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361579404.

The product of its (nonzero) digits is 163296, while the sum is 41.

The spelling of 20971603634 in words is "twenty billion, nine hundred seventy-one million, six hundred three thousand, six hundred thirty-four".