20315321021 has 8 divisors (see below), whose sum is σ = 21200045760. Its totient is φ = 19430717152.

The previous prime is 20315321017. The next prime is 20315321023. The reversal of 20315321021 is 12012351302.

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 20315321021 - 2² = 20315321017 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20315320984 and 20315321002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20315321023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 552806 + ... + 588408.

It is an arithmetic number, because the mean of its divisors is an integer number (2650005720).

Almost surely, 2^20315321021 is an apocalyptic number.

It is an amenable number.

20315321021 is a deficient number, since it is larger than the sum of its proper divisors (884724739).

20315321021 is a wasteful number, since it uses less digits than its factorization.

20315321021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60435.

The product of its (nonzero) digits is 360, while the sum is 20.

Adding to 20315321021 its reverse (12012351302), we get a palindrome (32327672323).

The spelling of 20315321021 in words is "twenty billion, three hundred fifteen million, three hundred twenty-one thousand, twenty-one".