21035052 has 144 divisors (see below), whose sum is σ = 62375040. Its totient is φ = 6158592.

The previous prime is 21035029. The next prime is 21035059. The reversal of 21035052 is 25053012.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (21035059) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 313923 + ... + 313989.

It is an arithmetic number, because the mean of its divisors is an integer number (433160).

Almost surely, 2^21035052 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 21035052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31187520).

21035052 is an abundant number, since it is smaller than the sum of its proper divisors (41339988).

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

21035052 is a wasteful number, since it uses less digits than its factorization.

21035052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

The square root of 21035052 is about 4586.3985871269. The cubic root of 21035052 is about 276.0458335981.

Adding to 21035052 its reverse (25053012), we get a palindrome (46088064).

The spelling of 21035052 in words is "twenty-one million, thirty-five thousand, fifty-two".