21113031077 has 2 divisors, whose sum is σ = 21113031078. Its totient is φ = 21113031076.

The previous prime is 21113030959. The next prime is 21113031083. The reversal of 21113031077 is 77013031112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14021875396 + 7091155681 = 118414^2 + 84209^2 .

It is a cyclic number.

It is not a de Polignac number, because 21113031077 - 2¹⁸ = 21112768933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21113031377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556515538 + 10556515539.

It is an arithmetic number, because the mean of its divisors is an integer number (10556515539).

Almost surely, 2^21113031077 is an apocalyptic number.

It is an amenable number.

21113031077 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113031077 is an equidigital number, since it uses as much as digits as its factorization.

21113031077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 882, while the sum is 26.

Adding to 21113031077 its reverse (77013031112), we get a palindrome (98126062189).

The spelling of 21113031077 in words is "twenty-one billion, one hundred thirteen million, thirty-one thousand, seventy-seven".