21121164227 has 8 divisors (see below), whose sum is σ = 21655731552. Its totient is φ = 20587521600.

The previous prime is 21121164193. The next prime is 21121164257. The reversal of 21121164227 is 72246112112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21121164227 - 2²⁴ = 21104387011 is a prime.

It is a super-2 number, since 2×21121164227² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21121164227.

It is not an unprimeable number, because it can be changed into a prime (21121164257) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 184799 + ... + 276392.

It is an arithmetic number, because the mean of its divisors is an integer number (2706966444).

Almost surely, 2^21121164227 is an apocalyptic number.

21121164227 is a deficient number, since it is larger than the sum of its proper divisors (534567325).

21121164227 is a wasteful number, since it uses less digits than its factorization.

21121164227 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462349.

The product of its digits is 2688, while the sum is 29.

Adding to 21121164227 its reverse (72246112112), we get a palindrome (93367276339).

The spelling of 21121164227 in words is "twenty-one billion, one hundred twenty-one million, one hundred sixty-four thousand, two hundred twenty-seven".