21773532 has 96 divisors (see below), whose sum is σ = 60770304. Its totient is φ = 5990400.

The previous prime is 21773527. The next prime is 21773533. The reversal of 21773532 is 23537712.

It is a self number, because there is not a number n which added to its sum of digits gives 21773532.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21773533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 69408 + ... + 69720.

It is an arithmetic number, because the mean of its divisors is an integer number (633024).

Almost surely, 2^21773532 is an apocalyptic number.

21773532 is a gapful number since it is divisible by the number (22) 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 21773532, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30385152).

21773532 is an abundant number, since it is smaller than the sum of its proper divisors (38996772).

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

21773532 is a wasteful number, since it uses less digits than its factorization.

21773532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379 (or 377 counting only the distinct ones).

The product of its digits is 8820, while the sum is 30.

The square root of 21773532 is about 4666.2117397306. The cubic root of 21773532 is about 279.2391418373.

The spelling of 21773532 in words is "twenty-one million, seven hundred seventy-three thousand, five hundred thirty-two".