212821536 has 48 divisors (see below), whose sum is σ = 559440000. Its totient is φ = 70841088.

The previous prime is 212821523. The next prime is 212821537. The reversal of 212821536 is 635128212.

It is a tau number, because it is divible by the number of its divisors (48).

It is not an unprimeable number, because it can be changed into a prime (212821537) 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 7 ways as a sum of consecutive naturals, for example, 105465 + ... + 107463.

It is an arithmetic number, because the mean of its divisors is an integer number (11655000).

Almost surely, 2^212821536 is an apocalyptic number.

It is an amenable number.

212821536 is an abundant number, since it is smaller than the sum of its proper divisors (346618464).

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

212821536 is a wasteful number, since it uses less digits than its factorization.

212821536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3121 (or 3113 counting only the distinct ones).

The product of its digits is 5760, while the sum is 30.

The square root of 212821536 is about 14588.4041622105. The cubic root of 212821536 is about 597.0424229622.

Adding to 212821536 its reverse (635128212), we get a palindrome (847949748).

The spelling of 212821536 in words is "two hundred twelve million, eight hundred twenty-one thousand, five hundred thirty-six".