221515412000 has 48 divisors (see below), whose sum is σ = 544263377112. Its totient is φ = 88606163200.

The previous prime is 221515411973. The next prime is 221515412023. The reversal of 221515412000 is 214515122.

It can be written as a sum of positive squares in 4 ways, for example, as 109341326224 + 112174085776 = 330668^2 + 334924^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27685427 + ... + 27693426.

Almost surely, 2^221515412000 is an apocalyptic number.

221515412000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221515412000 is an abundant number, since it is smaller than the sum of its proper divisors (322747965112).

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

221515412000 is an equidigital number, since it uses as much as digits as its factorization.

221515412000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55378878 (or 55378860 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 23.

Adding to 221515412000 its reverse (214515122), we get a palindrome (221729927122).

The spelling of 221515412000 in words is "two hundred twenty-one billion, five hundred fifteen million, four hundred twelve thousand".