21310211 has 8 divisors (see below), whose sum is σ = 22985424. Its totient is φ = 19640160.

The previous prime is 21310207. The next prime is 21310243. The reversal of 21310211 is 11201312.

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 21310211 - 2² = 21310207 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21310192 and 21310201.

It is not an unprimeable number, because it can be changed into a prime (21310271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14741 + ... + 16121.

It is an arithmetic number, because the mean of its divisors is an integer number (2873178).

Almost surely, 2^21310211 is an apocalyptic number.

21310211 is a deficient number, since it is larger than the sum of its proper divisors (1675213).

21310211 is a wasteful number, since it uses less digits than its factorization.

21310211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2581.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 21310211 is about 4616.2984088986. The cubic root of 21310211 is about 277.2442727016.

Adding to 21310211 its reverse (11201312), we get a palindrome (32511523).

The spelling of 21310211 in words is "twenty-one million, three hundred ten thousand, two hundred eleven".