21317101 has 8 divisors (see below), whose sum is σ = 23013144. Its totient is φ = 19629120.

The previous prime is 21317083. The next prime is 21317129. The reversal of 21317101 is 10171312.

It can be written as a sum of positive squares in 4 ways, for example, as 249001 + 21068100 = 499^2 + 4590^2 .

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 21317101 - 2¹¹ = 21315053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21317141) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 4215 + ... + 7771.

It is an arithmetic number, because the mean of its divisors is an integer number (2876643).

Almost surely, 2^21317101 is an apocalyptic number.

It is an amenable number.

21317101 is a deficient number, since it is larger than the sum of its proper divisors (1696043).

21317101 is a wasteful number, since it uses less digits than its factorization.

21317101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4031.

The product of its (nonzero) digits is 42, while the sum is 16.

The square root of 21317101 is about 4617.0446175015. The cubic root of 21317101 is about 277.2741489458.

Adding to 21317101 its reverse (10171312), we get a palindrome (31488413).

The spelling of 21317101 in words is "twenty-one million, three hundred seventeen thousand, one hundred one".