21031030 has 8 divisors (see below), whose sum is σ = 37855872. Its totient is φ = 8412408.

The previous prime is 21031027. The next prime is 21031033. The reversal of 21031030 is 3013012.

It is an interprime number because it is at equal distance from previous prime (21031027) and next prime (21031033).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (10), and also a Moran number because the ratio is a prime number: 2103103 = 21031030 / (2 + 1 + 0 + 3 + 1 + 0 + 3 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 21030998 and 21031016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031033) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1051542 + ... + 1051561.

It is an arithmetic number, because the mean of its divisors is an integer number (4731984).

Almost surely, 2^21031030 is an apocalyptic number.

21031030 is a deficient number, since it is larger than the sum of its proper divisors (16824842).

21031030 is a wasteful number, since it uses less digits than its factorization.

21031030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2103110.

The product of its (nonzero) digits is 18, while the sum is 10.

The square root of 21031030 is about 4585.9600957706. The cubic root of 21031030 is about 276.0282387266.

Adding to 21031030 its reverse (3013012), we get a palindrome (24044042).

The spelling of 21031030 in words is "twenty-one million, thirty-one thousand, thirty".