21110075251 has 2 divisors, whose sum is σ = 21110075252. Its totient is φ = 21110075250.

The previous prime is 21110075243. The next prime is 21110075293. The reversal of 21110075251 is 15257001112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21110075251 - 2³ = 21110075243 is a prime.

It is not a weakly prime, because it can be changed into another prime (21110075351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555037625 + 10555037626.

It is an arithmetic number, because the mean of its divisors is an integer number (10555037626).

Almost surely, 2^21110075251 is an apocalyptic number.

21110075251 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110075251 is an equidigital number, since it uses as much as digits as its factorization.

21110075251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 700, while the sum is 25.

Adding to 21110075251 its reverse (15257001112), we get a palindrome (36367076363).

The spelling of 21110075251 in words is "twenty-one billion, one hundred ten million, seventy-five thousand, two hundred fifty-one".