2155221415 has 8 divisors (see below), whose sum is σ = 2635063488. Its totient is φ = 1691645280.

The previous prime is 2155221403. The next prime is 2155221421. The reversal of 2155221415 is 5141225512.

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

It is not a de Polignac number, because 2155221415 - 2¹³ = 2155213223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4066191 + ... + 4066720.

It is an arithmetic number, because the mean of its divisors is an integer number (329382936).

Almost surely, 2^2155221415 is an apocalyptic number.

2155221415 is a deficient number, since it is larger than the sum of its proper divisors (479842073).

2155221415 is an equidigital number, since it uses as much as digits as its factorization.

2155221415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8132969.

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

The square root of 2155221415 is about 46424.3623004129. The cubic root of 2155221415 is about 1291.7068556255.

Adding to 2155221415 its reverse (5141225512), we get a palindrome (7296446927).

The spelling of 2155221415 in words is "two billion, one hundred fifty-five million, two hundred twenty-one thousand, four hundred fifteen".