21012003284 has 6 divisors (see below), whose sum is σ = 36771005754. Its totient is φ = 10506001640.

The previous prime is 21012003283. The next prime is 21012003323. The reversal of 21012003284 is 48230021012.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20342746384 + 669256900 = 142628^2 + 25870^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012003283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2626500407 + ... + 2626500414.

It is an arithmetic number, because the mean of its divisors is an integer number (6128500959).

Almost surely, 2^21012003284 is an apocalyptic number.

It is an amenable number.

21012003284 is a deficient number, since it is larger than the sum of its proper divisors (15759002470).

21012003284 is a wasteful number, since it uses less digits than its factorization.

21012003284 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5253000825 (or 5253000823 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

Adding to 21012003284 its reverse (48230021012), we get a palindrome (69242024296).

The spelling of 21012003284 in words is "twenty-one billion, twelve million, three thousand, two hundred eighty-four".