21155022311 has 2 divisors, whose sum is σ = 21155022312. Its totient is φ = 21155022310.

The previous prime is 21155022299. The next prime is 21155022397. The reversal of 21155022311 is 11322055112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21155022311 - 2⁶ = 21155022247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21155024311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577511155 + 10577511156.

It is an arithmetic number, because the mean of its divisors is an integer number (10577511156).

Almost surely, 2^21155022311 is an apocalyptic number.

21155022311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21155022311 is an equidigital number, since it uses as much as digits as its factorization.

21155022311 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 600, while the sum is 23.

Adding to 21155022311 its reverse (11322055112), we get a palindrome (32477077423).

The spelling of 21155022311 in words is "twenty-one billion, one hundred fifty-five million, twenty-two thousand, three hundred eleven".