20421921952 has 24 divisors (see below), whose sum is σ = 40461755796. Its totient is φ = 10145920512.

The previous prime is 20421921929. The next prime is 20421921977. The reversal of 20421921952 is 25912912402.

It can be written as a sum of positive squares in 2 ways, for example, as 16826240656 + 3595681296 = 129716^2 + 59964^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2027413 + ... + 2037460.

Almost surely, 2^20421921952 is an apocalyptic number.

It is an amenable number.

20421921952 is a deficient number, since it is larger than the sum of its proper divisors (20039833844).

20421921952 is a wasteful number, since it uses less digits than its factorization.

20421921952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4065040 (or 4065032 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

The spelling of 20421921952 in words is "twenty billion, four hundred twenty-one million, nine hundred twenty-one thousand, nine hundred fifty-two".