21144235450 has 96 divisors (see below), whose sum is σ = 43807196160. Its totient is φ = 7543411200.

The previous prime is 21144235433. The next prime is 21144235459. The reversal of 21144235450 is 5453244112.

It is not an unprimeable number, because it can be changed into a prime (21144235459) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2409070 + ... + 2417830.

It is an arithmetic number, because the mean of its divisors is an integer number (456324960).

Almost surely, 2^21144235450 is an apocalyptic number.

21144235450 is an abundant number, since it is smaller than the sum of its proper divisors (22662960710).

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

21144235450 is a wasteful number, since it uses less digits than its factorization.

21144235450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8912 (or 8907 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 31.

Adding to 21144235450 its reverse (5453244112), we get a palindrome (26597479562).

The spelling of 21144235450 in words is "twenty-one billion, one hundred forty-four million, two hundred thirty-five thousand, four hundred fifty".