21210031230 has 64 divisors (see below), whose sum is σ = 51768972288. Its totient is φ = 5560018560.

The previous prime is 21210031163. The next prime is 21210031307. The reversal of 21210031230 is 3213001212.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6115957 + ... + 6119423.

It is an arithmetic number, because the mean of its divisors is an integer number (808890192).

Almost surely, 2^21210031230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21210031230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25884486144).

21210031230 is an abundant number, since it is smaller than the sum of its proper divisors (30558941058).

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

21210031230 is a wasteful number, since it uses less digits than its factorization.

21210031230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6881.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21210031230 its reverse (3213001212), we get a palindrome (24423032442).

The spelling of 21210031230 in words is "twenty-one billion, two hundred ten million, thirty-one thousand, two hundred thirty".