21733020 has 36 divisors (see below), whose sum is σ = 65924040. Its totient is φ = 5795424.

The previous prime is 21733013. The next prime is 21733027. The reversal of 21733020 is 2033712.

It is an interprime number because it is at equal distance from previous prime (21733013) and next prime (21733027).

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 21732984 and 21733002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21733027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 60190 + ... + 60549.

Almost surely, 2^21733020 is an apocalyptic number.

21733020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21733020 is an abundant number, since it is smaller than the sum of its proper divisors (44191020).

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

21733020 is a wasteful number, since it uses less digits than its factorization.

21733020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120754 (or 120749 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 18.

The square root of 21733020 is about 4661.8687240204. The cubic root of 21733020 is about 279.0658494896.

Adding to 21733020 its reverse (2033712), we get a palindrome (23766732).

The spelling of 21733020 in words is "twenty-one million, seven hundred thirty-three thousand, twenty".