21623000 has 64 divisors (see below), whose sum is σ = 57844800. Its totient is φ = 7411200.

The previous prime is 21622999. The next prime is 21623057. The reversal of 21623000 is 32612.

It is a Harshad number since it is a multiple of its sum of digits (14).

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, 5456 + ... + 8544.

It is an arithmetic number, because the mean of its divisors is an integer number (903825).

Almost surely, 2^21623000 is an apocalyptic number.

21623000 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 21623000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28922400).

21623000 is an abundant number, since it is smaller than the sum of its proper divisors (36221800).

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

21623000 is a wasteful number, since it uses less digits than its factorization.

21623000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3117 (or 3103 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21623000 is about 4650.0537631301. The cubic root of 21623000 is about 278.5941436034.

Adding to 21623000 its reverse (32612), we get a palindrome (21655612).

The spelling of 21623000 in words is "twenty-one million, six hundred twenty-three thousand".