21436000 has 96 divisors (see below), whose sum is σ = 55194048. Its totient is φ = 8166400.

The previous prime is 21435991. The next prime is 21436001. The reversal of 21436000 is 63412.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 91884 + ... + 92116.

It is an arithmetic number, because the mean of its divisors is an integer number (574938).

Almost surely, 2^21436000 is an apocalyptic number.

21436000 is a gapful number since it is divisible by the number (20) 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 21436000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27597024).

21436000 is an abundant number, since it is smaller than the sum of its proper divisors (33758048).

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

21436000 is a wasteful number, since it uses less digits than its factorization.

21436000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281 (or 263 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21436000 is about 4629.9028067552. The cubic root of 21436000 is about 277.7887047553.

Adding to 21436000 its reverse (63412), we get a palindrome (21499412).

The spelling of 21436000 in words is "twenty-one million, four hundred thirty-six thousand".