21155281127 has 2 divisors, whose sum is σ = 21155281128. Its totient is φ = 21155281126.

The previous prime is 21155281109. The next prime is 21155281141. The reversal of 21155281127 is 72118255112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21155281127 - 2⁸ = 21155280871 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21155281157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577640563 + 10577640564.

It is an arithmetic number, because the mean of its divisors is an integer number (10577640564).

Almost surely, 2^21155281127 is an apocalyptic number.

21155281127 is a deficient number, since it is larger than the sum of its proper divisors (1).

21155281127 is an equidigital number, since it uses as much as digits as its factorization.

21155281127 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11200, while the sum is 35.

The spelling of 21155281127 in words is "twenty-one billion, one hundred fifty-five million, two hundred eighty-one thousand, one hundred twenty-seven".