21221052014550 has 48 divisors (see below), whose sum is σ = 55398114740160. Its totient is φ = 5361107876640.

The previous prime is 21221052014549. The next prime is 21221052014557. The reversal of 21221052014550 is 5541025012212.

It is a super-2 number, since 2×21221052014550² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221052014557) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3722988732 + ... + 3722994431.

It is an arithmetic number, because the mean of its divisors is an integer number (1154127390420).

Almost surely, 2^{21221052014550} is an apocalyptic number.

21221052014550 is an abundant number, since it is smaller than the sum of its proper divisors (34177062725610).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21221052014550 is a wasteful number, since it uses less digits than its factorization.

21221052014550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7445983197 (or 7445983192 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 30.

Adding to 21221052014550 its reverse (5541025012212), we get a palindrome (26762077026762).

The spelling of 21221052014550 in words is "twenty-one trillion, two hundred twenty-one billion, fifty-two million, fourteen thousand, five hundred fifty".