21476 has 24 divisors (see below), whose sum is σ = 47040. Its totient is φ = 8352.

The previous prime is 21467. The next prime is 21481. The reversal of 21476 is 67412.

It is a super-2 number, since 2×21476² = 922437152, which contains 22 as substring.

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 21476.

It is an unprimeable number.

21476 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335 + ... + 393.

It is an arithmetic number, because the mean of its divisors is an integer number (1960).

2²¹⁴⁷⁶ is an apocalyptic number.

21476 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21476, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23520).

21476 is an abundant number, since it is smaller than the sum of its proper divisors (25564).

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

21476 is a wasteful number, since it uses less digits than its factorization.

21476 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 81 counting only the distinct ones).

The product of its digits is 336, while the sum is 20.

The square root of 21476 is about 146.5469208138. The cubic root of 21476 is about 27.7961383798.

Adding to 21476 its product of digits (336), we get a palindrome (21812).

Adding to 21476 its reverse (67412), we get a palindrome (88888).

The spelling of 21476 in words is "twenty-one thousand, four hundred seventy-six".