215321723426 has 36 divisors (see below), whose sum is σ = 348880324086. Its totient is φ = 99657550080.

The previous prime is 215321723413. The next prime is 215321723467. The reversal of 215321723426 is 624327123512.

It can be written as a sum of positive squares in only one way, i.e., 162284094025 + 53037629401 = 402845^2 + 230299^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 215321723426.

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 17 ways as a sum of consecutive naturals, for example, 910850 + ... + 1122626.

Almost surely, 2^215321723426 is an apocalyptic number.

215321723426 is a deficient number, since it is larger than the sum of its proper divisors (133558600660).

215321723426 is a wasteful number, since it uses less digits than its factorization.

215321723426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211887 (or 211833 counting only the distinct ones).

The product of its digits is 120960, while the sum is 38.

Adding to 215321723426 its reverse (624327123512), we get a palindrome (839648846938).

The spelling of 215321723426 in words is "two hundred fifteen billion, three hundred twenty-one million, seven hundred twenty-three thousand, four hundred twenty-six".