21110020277 has 2 divisors, whose sum is σ = 21110020278. Its totient is φ = 21110020276.

The previous prime is 21110020231. The next prime is 21110020297. The reversal of 21110020277 is 77202001112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15437068516 + 5672951761 = 124246^2 + 75319^2 .

It is a cyclic number.

It is not a de Polignac number, because 21110020277 - 2¹² = 21110016181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21110020297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555010138 + 10555010139.

It is an arithmetic number, because the mean of its divisors is an integer number (10555010139).

Almost surely, 2^21110020277 is an apocalyptic number.

It is an amenable number.

21110020277 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110020277 is an equidigital number, since it uses as much as digits as its factorization.

21110020277 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 392, while the sum is 23.

Adding to 21110020277 its reverse (77202001112), we get a palindrome (98312021389).

The spelling of 21110020277 in words is "twenty-one billion, one hundred ten million, twenty thousand, two hundred seventy-seven".