15530450221 has 16 divisors (see below), whose sum is σ = 18257738688. Its totient is φ = 13023849600.

The previous prime is 15530450219. The next prime is 15530450231. The reversal of 15530450221 is 12205403551.

It is a cyclic number.

It is not a de Polignac number, because 15530450221 - 2¹ = 15530450219 is a prime.

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 15530450221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15530450231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 183465 + ... + 254401.

It is an arithmetic number, because the mean of its divisors is an integer number (1141108668).

Almost surely, 2^15530450221 is an apocalyptic number.

15530450221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15530450221 is a deficient number, since it is larger than the sum of its proper divisors (2727288467).

15530450221 is a wasteful number, since it uses less digits than its factorization.

15530450221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72492.

The product of its (nonzero) digits is 6000, while the sum is 28.

Adding to 15530450221 its reverse (12205403551), we get a palindrome (27735853772).

The spelling of 15530450221 in words is "fifteen billion, five hundred thirty million, four hundred fifty thousand, two hundred twenty-one".