21548101111 has 2 divisors, whose sum is σ = 21548101112. Its totient is φ = 21548101110.

The previous prime is 21548101093. The next prime is 21548101117. The reversal of 21548101111 is 11110184512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21548101111 - 2⁷ = 21548100983 is a prime.

It is a super-2 number, since 2×21548101111² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21548101117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10774050555 + 10774050556.

It is an arithmetic number, because the mean of its divisors is an integer number (10774050556).

Almost surely, 2^21548101111 is an apocalyptic number.

21548101111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21548101111 is an equidigital number, since it uses as much as digits as its factorization.

21548101111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 320, while the sum is 25.

Adding to 21548101111 its reverse (11110184512), we get a palindrome (32658285623).

The spelling of 21548101111 in words is "twenty-one billion, five hundred forty-eight million, one hundred one thousand, one hundred eleven".