21321212310 has 64 divisors (see below), whose sum is σ = 57197145600. Its totient is φ = 5651598816.

The previous prime is 21321212309. The next prime is 21321212327. The reversal of 21321212310 is 1321212312.

21321212310 is a `hidden beast` number, since 21 + 321 + 2 + 12 + 310 = 666.

It is a super-2 number, since 2×21321212310² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 191340 + ... + 281519.

It is an arithmetic number, because the mean of its divisors is an integer number (893705400).

Almost surely, 2^21321212310 is an apocalyptic number.

21321212310 is an abundant number, since it is smaller than the sum of its proper divisors (35875933290).

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

21321212310 is a wasteful number, since it uses less digits than its factorization.

21321212310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473042 (or 473036 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21321212310 its reverse (1321212312), we get a palindrome (22642424622).

It can be divided in two parts, 213212 and 12310, that added together give a palindrome (225522).

The spelling of 21321212310 in words is "twenty-one billion, three hundred twenty-one million, two hundred twelve thousand, three hundred ten".