21602350740505 has 4 divisors (see below), whose sum is σ = 25922820888612. Its totient is φ = 17281880592400.

The previous prime is 21602350740491. The next prime is 21602350740563. The reversal of 21602350740505 is 50504705320612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3840079190544 + 17762271549961 = 1959612^2 + 4214531^2 .

It is not a de Polignac number, because 21602350740505 - 2²⁹ = 21601813869593 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

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, 2160235074046 + ... + 2160235074055.

It is an arithmetic number, because the mean of its divisors is an integer number (6480705222153).

Almost surely, 2^{21602350740505} is an apocalyptic number.

It is an amenable number.

21602350740505 is a deficient number, since it is larger than the sum of its proper divisors (4320470148107).

21602350740505 is an equidigital number, since it uses as much as digits as its factorization.

21602350740505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4320470148106.

The product of its (nonzero) digits is 252000, while the sum is 40.

The spelling of 21602350740505 in words is "twenty-one trillion, six hundred two billion, three hundred fifty million, seven hundred forty thousand, five hundred five".