21320101 has 4 divisors (see below), whose sum is σ = 23258304. Its totient is φ = 19381900.

The previous prime is 21320099. The next prime is 21320107. The reversal of 21320101 is 10102312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21320101 - 2¹ = 21320099 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 (21320107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 969085 + ... + 969106.

It is an arithmetic number, because the mean of its divisors is an integer number (5814576).

Almost surely, 2^21320101 is an apocalyptic number.

It is an amenable number.

21320101 is a deficient number, since it is larger than the sum of its proper divisors (1938203).

21320101 is a wasteful number, since it uses less digits than its factorization.

21320101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1938202.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 21320101 is about 4617.3694892222. The cubic root of 21320101 is about 277.2871554584.

Adding to 21320101 its reverse (10102312), we get a palindrome (31422413).

The spelling of 21320101 in words is "twenty-one million, three hundred twenty thousand, one hundred one".