1223100020 has 72 divisors (see below), whose sum is σ = 2774015160. Its totient is φ = 452782080.

The previous prime is 1223100017. The next prime is 1223100077. The reversal of 1223100020 is 200013221.

It is a happy number.

It can be written as a sum of positive squares in 12 ways, for example, as 603488356 + 619611664 = 24566^2 + 24892^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1223099974 and 1223100010.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 350846 + ... + 354314.

Almost surely, 2^1223100020 is an apocalyptic number.

1223100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1223100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1387007580).

1223100020 is an abundant number, since it is smaller than the sum of its proper divisors (1550915140).

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

1223100020 is a wasteful number, since it uses less digits than its factorization.

1223100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3573 (or 3554 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 1223100020 is about 34972.8468958419. The cubic root of 1223100020 is about 1069.4340093378.

Adding to 1223100020 its reverse (200013221), we get a palindrome (1423113241).

The spelling of 1223100020 in words is "one billion, two hundred twenty-three million, one hundred thousand, twenty".