2106620251 has 2 divisors, whose sum is σ = 2106620252. Its totient is φ = 2106620250.

The previous prime is 2106620249. The next prime is 2106620273. The reversal of 2106620251 is 1520266012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2106620251 - 2¹ = 2106620249 is a prime.

Together with 2106620249, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2106620281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1053310125 + 1053310126.

It is an arithmetic number, because the mean of its divisors is an integer number (1053310126).

Almost surely, 2^2106620251 is an apocalyptic number.

2106620251 is a deficient number, since it is larger than the sum of its proper divisors (1).

2106620251 is an equidigital number, since it uses as much as digits as its factorization.

2106620251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 2106620251 is about 45897.9329708866. The cubic root of 2106620251 is about 1281.9234288539.

Adding to 2106620251 its reverse (1520266012), we get a palindrome (3626886263).

The spelling of 2106620251 in words is "two billion, one hundred six million, six hundred twenty thousand, two hundred fifty-one".