31203223212 has 48 divisors (see below), whose sum is σ = 83631018240. Its totient is φ = 8869947072.

The previous prime is 31203223193. The next prime is 31203223213. The reversal of 31203223212 is 21232230213.

It is a happy number.

It is a super-2 number, since 2×31203223212² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (31203223213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 926262 + ... + 959357.

It is an arithmetic number, because the mean of its divisors is an integer number (1742312880).

Almost surely, 2^31203223212 is an apocalyptic number.

It is an amenable number.

31203223212 is an abundant number, since it is smaller than the sum of its proper divisors (52427795028).

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

31203223212 is a wasteful number, since it uses less digits than its factorization.

31203223212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1885830 (or 1885828 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 31203223212 its reverse (21232230213), we get a palindrome (52435453425).

The spelling of 31203223212 in words is "thirty-one billion, two hundred three million, two hundred twenty-three thousand, two hundred twelve".