1221113020 has 12 divisors (see below), whose sum is σ = 2564337384. Its totient is φ = 488445200.

The previous prime is 1221113017. The next prime is 1221113041. The reversal of 1221113020 is 203111221.

It is a super-2 number, since 2×1221113020² = 2982234015227040800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30527806 + ... + 30527845.

It is an arithmetic number, because the mean of its divisors is an integer number (213694782).

Almost surely, 2^1221113020 is an apocalyptic number.

1221113020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221113020 is an abundant number, since it is smaller than the sum of its proper divisors (1343224364).

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

1221113020 is a wasteful number, since it uses less digits than its factorization.

1221113020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61055660 (or 61055658 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1221113020 is about 34944.4275958271. The cubic root of 1221113020 is about 1068.8545753604.

Adding to 1221113020 its reverse (203111221), we get a palindrome (1424224241).

The spelling of 1221113020 in words is "one billion, two hundred twenty-one million, one hundred thirteen thousand, twenty".