1221011420 has 12 divisors (see below), whose sum is σ = 2564124024. Its totient is φ = 488404560.

The previous prime is 1221011413. The next prime is 1221011437. The reversal of 1221011420 is 241101221.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1221011395 and 1221011404.

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, 30525266 + ... + 30525305.

It is an arithmetic number, because the mean of its divisors is an integer number (213677002).

Almost surely, 2^1221011420 is an apocalyptic number.

1221011420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221011420 is an abundant number, since it is smaller than the sum of its proper divisors (1343112604).

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

1221011420 is a wasteful number, since it uses less digits than its factorization.

1221011420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61050580 (or 61050578 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1221011420 is about 34942.9738287971. The cubic root of 1221011420 is about 1068.8249306470.

Adding to 1221011420 its reverse (241101221), we get a palindrome (1462112641).

The spelling of 1221011420 in words is "one billion, two hundred twenty-one million, eleven thousand, four hundred twenty".