20321221985 has 8 divisors (see below), whose sum is σ = 24490126440. Its totient is φ = 16187204224.

The previous prime is 20321221957. The next prime is 20321222011. The reversal of 20321221985 is 58912212302.

It can be written as a sum of positive squares in 4 ways, for example, as 1145619409 + 19175602576 = 33847^2 + 138476^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20321221985 - 2⁸ = 20321221729 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8720390 + ... + 8722719.

It is an arithmetic number, because the mean of its divisors is an integer number (3061265805).

Almost surely, 2^20321221985 is an apocalyptic number.

It is an amenable number.

20321221985 is a deficient number, since it is larger than the sum of its proper divisors (4168904455).

20321221985 is a wasteful number, since it uses less digits than its factorization.

20321221985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17443347.

The product of its (nonzero) digits is 17280, while the sum is 35.

The spelling of 20321221985 in words is "twenty billion, three hundred twenty-one million, two hundred twenty-one thousand, nine hundred eighty-five".