2101211251 has 2 divisors, whose sum is σ = 2101211252. Its totient is φ = 2101211250.

The previous prime is 2101211249. The next prime is 2101211267. The reversal of 2101211251 is 1521121012.

It is an a-pointer prime, because the next prime (2101211267) can be obtained adding 2101211251 to its sum of digits (16).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2101211251 - 2¹ = 2101211249 is a prime.

Together with 2101211249, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2101211291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050605625 + 1050605626.

It is an arithmetic number, because the mean of its divisors is an integer number (1050605626).

Almost surely, 2^2101211251 is an apocalyptic number.

2101211251 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101211251 is an equidigital number, since it uses as much as digits as its factorization.

2101211251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40, while the sum is 16.

The square root of 2101211251 is about 45838.9708763188. The cubic root of 2101211251 is about 1280.8253244592.

Adding to 2101211251 its reverse (1521121012), we get a palindrome (3622332263).

The spelling of 2101211251 in words is "two billion, one hundred one million, two hundred eleven thousand, two hundred fifty-one".