1012121220 has 48 divisors (see below), whose sum is σ = 3091572288. Its totient is φ = 245362560.

The previous prime is 1012121207. The next prime is 1012121221. The reversal of 1012121220 is 221212101.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 1012121196 and 1012121205.

It is not an unprimeable number, because it can be changed into a prime (1012121221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 766099 + ... + 767418.

It is an arithmetic number, because the mean of its divisors is an integer number (64407756).

Almost surely, 2^1012121220 is an apocalyptic number.

1012121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1012121220 is an abundant number, since it is smaller than the sum of its proper divisors (2079451068).

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

1012121220 is a wasteful number, since it uses less digits than its factorization.

1012121220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1533540 (or 1533538 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1012121220 is about 31813.8526431490. The cubic root of 1012121220 is about 1004.0241908321.

Adding to 1012121220 its reverse (221212101), we get a palindrome (1233333321).

The spelling of 1012121220 in words is "one billion, twelve million, one hundred twenty-one thousand, two hundred twenty".