31221213330 has 16 divisors (see below), whose sum is σ = 74930912064. Its totient is φ = 8325656880.

The previous prime is 31221213319. The next prime is 31221213367. The reversal of 31221213330 is 3331212213.

It is a junction number, because it is equal to n+sod(n) for n = 31221213297 and 31221213306.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 520353526 + ... + 520353585.

It is an arithmetic number, because the mean of its divisors is an integer number (4683182004).

Almost surely, 2^31221213330 is an apocalyptic number.

31221213330 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31221213330 is an abundant number, since it is smaller than the sum of its proper divisors (43709698734).

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

31221213330 is a wasteful number, since it uses less digits than its factorization.

31221213330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1040707121.

The product of its (nonzero) digits is 648, while the sum is 21.

Adding to 31221213330 its reverse (3331212213), we get a palindrome (34552425543).

The spelling of 31221213330 in words is "thirty-one billion, two hundred twenty-one million, two hundred thirteen thousand, three hundred thirty".