212120310440 has 32 divisors (see below), whose sum is σ = 505345447080. Its totient is φ = 79857057792.

The previous prime is 212120310433. The next prime is 212120310443. The reversal of 212120310440 is 44013021212.

It can be written as a sum of positive squares in 4 ways, for example, as 135720033604 + 76400276836 = 368402^2 + 276406^2 .

It is a super-2 number, since 2×212120310440² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (212120310443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155970137 + ... + 155971496.

Almost surely, 2^212120310440 is an apocalyptic number.

212120310440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212120310440 is an abundant number, since it is smaller than the sum of its proper divisors (293225136640).

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

212120310440 is a wasteful number, since it uses less digits than its factorization.

212120310440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311941661 (or 311941657 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 212120310440 its reverse (44013021212), we get a palindrome (256133331652).

The spelling of 212120310440 in words is "two hundred twelve billion, one hundred twenty million, three hundred ten thousand, four hundred forty".