20315021213 has 2 divisors, whose sum is σ = 20315021214. Its totient is φ = 20315021212.

The previous prime is 20315021059. The next prime is 20315021227. The reversal of 20315021213 is 31212051302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18112314724 + 2202706489 = 134582^2 + 46933^2 .

It is a cyclic number.

It is not a de Polignac number, because 20315021213 - 2²² = 20310826909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20315021263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10157510606 + 10157510607.

It is an arithmetic number, because the mean of its divisors is an integer number (10157510607).

Almost surely, 2^20315021213 is an apocalyptic number.

It is an amenable number.

20315021213 is a deficient number, since it is larger than the sum of its proper divisors (1).

20315021213 is an equidigital number, since it uses as much as digits as its factorization.

20315021213 is an odious number, because the sum of its binary digits is odd.

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

Adding to 20315021213 its reverse (31212051302), we get a palindrome (51527072515).

The spelling of 20315021213 in words is "twenty billion, three hundred fifteen million, twenty-one thousand, two hundred thirteen".