21221021010111 has 16 divisors (see below), whose sum is σ = 30471597112320. Its totient is φ = 13058923799520.

The previous prime is 21221021010083. The next prime is 21221021010127. The reversal of 21221021010111 is 11101012012212.

It is a happy number.

It is not a de Polignac number, because 21221021010111 - 2¹³ = 21221021001919 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221021010151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 316855 + ... + 6522456.

It is an arithmetic number, because the mean of its divisors is an integer number (1904474819520).

Almost surely, 2^{21221021010111} is an apocalyptic number.

21221021010111 is a deficient number, since it is larger than the sum of its proper divisors (9250576102209).

21221021010111 is a wasteful number, since it uses less digits than its factorization.

21221021010111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6918886.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21221021010111 its reverse (11101012012212), we get a palindrome (32322033022323).

The spelling of 21221021010111 in words is "twenty-one trillion, two hundred twenty-one billion, twenty-one million, ten thousand, one hundred eleven".