21100222051 has 2 divisors, whose sum is σ = 21100222052. Its totient is φ = 21100222050.

The previous prime is 21100222043. The next prime is 21100222063. The reversal of 21100222051 is 15022200112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21100222051 - 2³ = 21100222043 is a prime.

It is not a weakly prime, because it can be changed into another prime (21100222081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550111025 + 10550111026.

It is an arithmetic number, because the mean of its divisors is an integer number (10550111026).

Almost surely, 2^21100222051 is an apocalyptic number.

21100222051 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100222051 is an equidigital number, since it uses as much as digits as its factorization.

21100222051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80, while the sum is 16.

Adding to 21100222051 its reverse (15022200112), we get a palindrome (36122422163).

The spelling of 21100222051 in words is "twenty-one billion, one hundred million, two hundred twenty-two thousand, fifty-one".