20312555321 has 4 divisors (see below), whose sum is σ = 21381637200. Its totient is φ = 19243473444.

The previous prime is 20312555311. The next prime is 20312555323. The reversal of 20312555321 is 12355521302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12355521302 = 2 ⋅6177760651.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20312555321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20312555323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 534540911 + ... + 534540948.

It is an arithmetic number, because the mean of its divisors is an integer number (5345409300).

Almost surely, 2^20312555321 is an apocalyptic number.

It is an amenable number.

20312555321 is a deficient number, since it is larger than the sum of its proper divisors (1069081879).

20312555321 is a wasteful number, since it uses less digits than its factorization.

20312555321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1069081878.

The product of its (nonzero) digits is 9000, while the sum is 29.

The spelling of 20312555321 in words is "twenty billion, three hundred twelve million, five hundred fifty-five thousand, three hundred twenty-one".