1220100020 has 12 divisors (see below), whose sum is σ = 2562210084. Its totient is φ = 488040000.

The previous prime is 1220099989. The next prime is 1220100023. The reversal of 1220100020 is 200010221.

It can be written as a sum of positive squares in 2 ways, for example, as 605258404 + 614841616 = 24602^2 + 24796^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1220099980 and 1220100007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220100023) 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 3 ways as a sum of consecutive naturals, for example, 30502481 + ... + 30502520.

It is an arithmetic number, because the mean of its divisors is an integer number (213517507).

Almost surely, 2^1220100020 is an apocalyptic number.

1220100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1220100020 is an abundant number, since it is smaller than the sum of its proper divisors (1342110064).

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

1220100020 is a wasteful number, since it uses less digits than its factorization.

1220100020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61005010 (or 61005008 counting only the distinct ones).

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

The square root of 1220100020 is about 34929.9301459365. The cubic root of 1220100020 is about 1068.5589299913.

Adding to 1220100020 its reverse (200010221), we get a palindrome (1420110241).

The spelling of 1220100020 in words is "one billion, two hundred twenty million, one hundred thousand, twenty".