210031213121 has 2 divisors, whose sum is σ = 210031213122. Its totient is φ = 210031213120.

The previous prime is 210031213109. The next prime is 210031213127. The reversal of 210031213121 is 121312130012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 205898137600 + 4133075521 = 453760^2 + 64289^2 .

It is a cyclic number.

It is not a de Polignac number, because 210031213121 - 2⁶ = 210031213057 is a prime.

It is a super-2 number, since 2×210031213121² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 210031213121.

It is not a weakly prime, because it can be changed into another prime (210031213127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105015606560 + 105015606561.

It is an arithmetic number, because the mean of its divisors is an integer number (105015606561).

Almost surely, 2^210031213121 is an apocalyptic number.

It is an amenable number.

210031213121 is a deficient number, since it is larger than the sum of its proper divisors (1).

210031213121 is an equidigital number, since it uses as much as digits as its factorization.

210031213121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 210031213121 its reverse (121312130012), we get a palindrome (331343343133).

The spelling of 210031213121 in words is "two hundred ten billion, thirty-one million, two hundred thirteen thousand, one hundred twenty-one".