21013532 has 6 divisors (see below), whose sum is σ = 36773688. Its totient is φ = 10506764.

The previous prime is 21013529. The next prime is 21013537. The reversal of 21013532 is 23531012.

It is a self number, because there is not a number n which added to its sum of digits gives 21013532.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2626688 + ... + 2626695.

It is an arithmetic number, because the mean of its divisors is an integer number (6128948).

Almost surely, 2^21013532 is an apocalyptic number.

It is an amenable number.

21013532 is a deficient number, since it is larger than the sum of its proper divisors (15760156).

21013532 is a wasteful number, since it uses less digits than its factorization.

21013532 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5253387 (or 5253385 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 21013532 is about 4584.0519194267. The cubic root of 21013532 is about 275.9516648536.

Adding to 21013532 its reverse (23531012), we get a palindrome (44544544).

The spelling of 21013532 in words is "twenty-one million, thirteen thousand, five hundred thirty-two".