15420221515 has 8 divisors (see below), whose sum is σ = 18510183360. Its totient is φ = 12332232192.

The previous prime is 15420221507. The next prime is 15420221519. The reversal of 15420221515 is 51512202451.

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 15420221515 - 2³ = 15420221507 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15420221519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 475875 + ... + 507244.

It is an arithmetic number, because the mean of its divisors is an integer number (2313772920).

Almost surely, 2^15420221515 is an apocalyptic number.

15420221515 is a deficient number, since it is larger than the sum of its proper divisors (3089961845).

15420221515 is an equidigital number, since it uses as much as digits as its factorization.

15420221515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986261.

The product of its (nonzero) digits is 4000, while the sum is 28.

Adding to 15420221515 its reverse (51512202451), we get a palindrome (66932423966).

The spelling of 15420221515 in words is "fifteen billion, four hundred twenty million, two hundred twenty-one thousand, five hundred fifteen".