21210461312 has 16 divisors (see below), whose sum is σ = 42255216150. Its totient is φ = 10605230592.

The previous prime is 21210461309. The next prime is 21210461347. The reversal of 21210461312 is 21316401212.

It can be written as a sum of positive squares in only one way, i.e., 16513278016 + 4697183296 = 128504^2 + 68536^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×21210461312² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82853237 + ... + 82853492.

Almost surely, 2^21210461312 is an apocalyptic number.

It is an amenable number.

21210461312 is a deficient number, since it is larger than the sum of its proper divisors (21044754838).

21210461312 is an equidigital number, since it uses as much as digits as its factorization.

21210461312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165706743 (or 165706731 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 21210461312 its reverse (21316401212), we get a palindrome (42526862524).

The spelling of 21210461312 in words is "twenty-one billion, two hundred ten million, four hundred sixty-one thousand, three hundred twelve".