100012001220 has 72 divisors (see below), whose sum is σ = 311568939864. Its totient is φ = 25949058048.

The previous prime is 100012001207. The next prime is 100012001231. The reversal of 100012001220 is 22100210001.

It can be written as a sum of positive squares in 4 ways, for example, as 43018078464 + 56993922756 = 207408^2 + 238734^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 7501749 + ... + 7515068.

It is an arithmetic number, because the mean of its divisors is an integer number (4327346387).

Almost surely, 2^100012001220 is an apocalyptic number.

100012001220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

100012001220 is an abundant number, since it is smaller than the sum of its proper divisors (211556938644).

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

100012001220 is a wasteful number, since it uses less digits than its factorization.

100012001220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15016869 (or 15016864 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 100012001220 its reverse (22100210001), we get a palindrome (122112211221).

The spelling of 100012001220 in words is "one hundred billion, twelve million, one thousand, two hundred twenty".