1221026120 has 32 divisors (see below), whose sum is σ = 2748470400. Its totient is φ = 488203968.

The previous prime is 1221026101. The next prime is 1221026123. The reversal of 1221026120 is 216201221.

It is not an unprimeable number, because it can be changed into a prime (1221026123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 119867 + ... + 129653.

It is an arithmetic number, because the mean of its divisors is an integer number (85889700).

Almost surely, 2^1221026120 is an apocalyptic number.

1221026120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221026120 is an abundant number, since it is smaller than the sum of its proper divisors (1527444280).

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

1221026120 is a wasteful number, since it uses less digits than its factorization.

1221026120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12917 (or 12913 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1221026120 is about 34943.1841708794. The cubic root of 1221026120 is about 1068.8292198952.

Adding to 1221026120 its reverse (216201221), we get a palindrome (1437227341).

The spelling of 1221026120 in words is "one billion, two hundred twenty-one million, twenty-six thousand, one hundred twenty".