21018102 has 16 divisors (see below), whose sum is σ = 48041472. Its totient is φ = 6005160.

The previous prime is 21018097. The next prime is 21018133. The reversal of 21018102 is 20181012.

It is a super-2 number, since 2×21018102² = 883521223364808, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 250174 + ... + 250257.

It is an arithmetic number, because the mean of its divisors is an integer number (3002592).

Almost surely, 2^21018102 is an apocalyptic number.

21018102 is an abundant number, since it is smaller than the sum of its proper divisors (27023370).

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

21018102 is a wasteful number, since it uses less digits than its factorization.

21018102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500443.

The product of its (nonzero) digits is 32, while the sum is 15.

The square root of 21018102 is about 4584.5503596318. The cubic root of 21018102 is about 275.9716679592.

Adding to 21018102 its reverse (20181012), we get a palindrome (41199114).

The spelling of 21018102 in words is "twenty-one million, eighteen thousand, one hundred two".