21013002 has 24 divisors (see below), whose sum is σ = 45660420. Its totient is φ = 6984000.

The previous prime is 21012997. The next prime is 21013019. The reversal of 21013002 is 20031012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20711601 + 301401 = 4551^2 + 549^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5502 + ... + 8502.

Almost surely, 2^21013002 is an apocalyptic number.

21013002 is an abundant number, since it is smaller than the sum of its proper divisors (24647418).

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

21013002 is a wasteful number, since it uses less digits than its factorization.

21013002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3398 (or 3395 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 21013002 is about 4583.9941099439. The cubic root of 21013002 is about 275.9493448309.

Adding to 21013002 its reverse (20031012), we get a palindrome (41044014).

The spelling of 21013002 in words is "twenty-one million, thirteen thousand, two".