21102030 has 24 divisors (see below), whose sum is σ = 54865512. Its totient is φ = 5627184.

The previous prime is 21102023. The next prime is 21102047. The reversal of 21102030 is 3020112.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 117144 + ... + 117323.

It is an arithmetic number, because the mean of its divisors is an integer number (2286063).

Almost surely, 2^21102030 is an apocalyptic number.

21102030 is an abundant number, since it is smaller than the sum of its proper divisors (33763482).

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

21102030 is a wasteful number, since it uses less digits than its factorization.

21102030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234480 (or 234477 counting only the distinct ones).

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

The square root of 21102030 is about 4593.6945915026. The cubic root of 21102030 is about 276.3385102978.

Adding to 21102030 its reverse (3020112), we get a palindrome (24122142).

The spelling of 21102030 in words is "twenty-one million, one hundred two thousand, thirty".