21703164 has 48 divisors (see below), whose sum is σ = 59447808. Its totient is φ = 6032448.

The previous prime is 21703159. The next prime is 21703177. The reversal of 21703164 is 46130712.

It is a super-2 number, since 2×21703164² = 942054655221792, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 384 + ... + 6599.

It is an arithmetic number, because the mean of its divisors is an integer number (1238496).

Almost surely, 2^21703164 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21703164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29723904).

21703164 is an abundant number, since it is smaller than the sum of its proper divisors (37744644).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21703164 is a wasteful number, since it uses less digits than its factorization.

21703164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7034 (or 7032 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 21703164 is about 4658.6654741460. The cubic root of 21703164 is about 278.9380008946.

Adding to 21703164 its reverse (46130712), we get a palindrome (67833876).

The spelling of 21703164 in words is "twenty-one million, seven hundred three thousand, one hundred sixty-four".