21660536523242 has 8 divisors (see below), whose sum is σ = 32491150269732. Its totient is φ = 10830153100000.

The previous prime is 21660536523211. The next prime is 21660536523257. The reversal of 21660536523242 is 24232563506612.

It can be written as a sum of positive squares in 2 ways, for example, as 21130652982481 + 529883540761 = 4596809^2 + 727931^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57345509 + ... + 57721992.

Almost surely, 2^{21660536523242} is an apocalyptic number.

21660536523242 is a deficient number, since it is larger than the sum of its proper divisors (10830613746490).

21660536523242 is a wasteful number, since it uses less digits than its factorization.

21660536523242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115161624.

The product of its (nonzero) digits is 3110400, while the sum is 47.

The spelling of 21660536523242 in words is "twenty-one trillion, six hundred sixty billion, five hundred thirty-six million, five hundred twenty-three thousand, two hundred forty-two".