21496 has 8 divisors (see below), whose sum is σ = 40320. Its totient is φ = 10744.

The previous prime is 21493. The next prime is 21499. The reversal of 21496 is 69412.

It is an interprime number because it is at equal distance from previous prime (21493) and next prime (21499).

It is a tau number, because it is divible by the number of its divisors (8).

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1336 + ... + 1351.

It is an arithmetic number, because the mean of its divisors is an integer number (5040).

2²¹⁴⁹⁶ is an apocalyptic number.

It is an amenable number.

21496 is a deficient number, since it is larger than the sum of its proper divisors (18824).

21496 is a wasteful number, since it uses less digits than its factorization.

21496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2693 (or 2689 counting only the distinct ones).

The product of its digits is 432, while the sum is 22.

The square root of 21496 is about 146.6151424649. The cubic root of 21496 is about 27.8047642922.

It can be divided in two parts, 2 and 1496, that multiplied together give a palindrome (2992).

The spelling of 21496 in words is "twenty-one thousand, four hundred ninety-six".