1220121020 has 24 divisors (see below), whose sum is σ = 2673657504. Its totient is φ = 466828736.

The previous prime is 1220121017. The next prime is 1220121037. The reversal of 1220121020 is 201210221.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1220120992 and 1220121010.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1325759 + ... + 1326678.

It is an arithmetic number, because the mean of its divisors is an integer number (111402396).

Almost surely, 2^1220121020 is an apocalyptic number.

1220121020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1220121020 is an abundant number, since it is smaller than the sum of its proper divisors (1453536484).

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

1220121020 is a wasteful number, since it uses less digits than its factorization.

1220121020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2652469 (or 2652467 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1220121020 is about 34930.2307464466. The cubic root of 1220121020 is about 1068.5650605293.

Adding to 1220121020 its reverse (201210221), we get a palindrome (1421331241).

The spelling of 1220121020 in words is "one billion, two hundred twenty million, one hundred twenty-one thousand, twenty".