21031130 has 16 divisors (see below), whose sum is σ = 38029824. Its totient is φ = 8373840.

The previous prime is 21031111. The next prime is 21031151. The reversal of 21031130 is 3113012.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2486 + ... + 6945.

It is an arithmetic number, because the mean of its divisors is an integer number (2376864).

Almost surely, 2^21031130 is an apocalyptic number.

21031130 is a deficient number, since it is larger than the sum of its proper divisors (16998694).

21031130 is a wasteful number, since it uses less digits than its factorization.

21031130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9661.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21031130 is about 4585.9709986000. The cubic root of 21031130 is about 276.0286762195.

Adding to 21031130 its reverse (3113012), we get a palindrome (24144142).

The spelling of 21031130 in words is "twenty-one million, thirty-one thousand, one hundred thirty".