21073536 has 96 divisors (see below), whose sum is σ = 66193920. Its totient is φ = 6382080.

The previous prime is 21073519. The next prime is 21073553. The reversal of 21073536 is 63537012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21073519) and next prime (21073553).

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11841 + ... + 13503.

It is an arithmetic number, because the mean of its divisors is an integer number (689520).

Almost surely, 2^21073536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21073536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33096960).

21073536 is an abundant number, since it is smaller than the sum of its proper divisors (45120384).

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

21073536 is a wasteful number, since it uses less digits than its factorization.

21073536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1694 (or 1679 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 27.

The square root of 21073536 is about 4590.5921186705. The cubic root of 21073536 is about 276.2140746195.

It can be divided in two parts, 21073 and 536, that added together give a square (21609 = 147²).

The spelling of 21073536 in words is "twenty-one million, seventy-three thousand, five hundred thirty-six".