213113211021 has 6 divisors (see below), whose sum is σ = 307830193710. Its totient is φ = 142075474008.

The previous prime is 213113211019. The next prime is 213113211023. The reversal of 213113211021 is 120112311312.

213113211021 is a `hidden beast` number, since 2 + 1 + 311 + 321 + 10 + 21 = 666.

It is an interprime number because it is at equal distance from previous prime (213113211019) and next prime (213113211023).

It can be written as a sum of positive squares in only one way, i.e., 197322524100 + 15790686921 = 444210^2 + 125661^2 .

It is not a de Polignac number, because 213113211021 - 2¹ = 213113211019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 213113210985 and 213113211003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213113211023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11839622826 + ... + 11839622843.

It is an arithmetic number, because the mean of its divisors is an integer number (51305032285).

Almost surely, 2^213113211021 is an apocalyptic number.

It is an amenable number.

213113211021 is a deficient number, since it is larger than the sum of its proper divisors (94716982689).

213113211021 is a wasteful number, since it uses less digits than its factorization.

213113211021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23679245675 (or 23679245672 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 213113211021 its reverse (120112311312), we get a palindrome (333225522333).

The spelling of 213113211021 in words is "two hundred thirteen billion, one hundred thirteen million, two hundred eleven thousand, twenty-one".