21152402105 has 8 divisors (see below), whose sum is σ = 25385958600. Its totient is φ = 16919870976.

The previous prime is 21152402059. The next prime is 21152402119. The reversal of 21152402105 is 50120425112.

It can be written as a sum of positive squares in 4 ways, for example, as 11790485056 + 9361917049 = 108584^2 + 96757^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21152402105 - 2⁶ = 21152402041 is a prime.

It is a super-2 number, since 2×21152402105² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 210200 + ... + 294089.

It is an arithmetic number, because the mean of its divisors is an integer number (3173244825).

Almost surely, 2^21152402105 is an apocalyptic number.

It is an amenable number.

21152402105 is a deficient number, since it is larger than the sum of its proper divisors (4233556495).

21152402105 is an equidigital number, since it uses as much as digits as its factorization.

21152402105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512683.

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

Adding to 21152402105 its reverse (50120425112), we get a palindrome (71272827217).

The spelling of 21152402105 in words is "twenty-one billion, one hundred fifty-two million, four hundred two thousand, one hundred five".