1221011204 has 18 divisors (see below), whose sum is σ = 2485630350. Its totient is φ = 523290432.

The previous prime is 1221011177. The next prime is 1221011221. The reversal of 1221011204 is 4021101221.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1220104900 + 906304 = 34930^2 + 952^2 .

It is a Harshad number since it is a multiple of its sum of digits (14).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3114629 + ... + 3115020.

It is an arithmetic number, because the mean of its divisors is an integer number (138090575).

Almost surely, 2^1221011204 is an apocalyptic number.

1221011204 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1221011204 is an abundant number, since it is smaller than the sum of its proper divisors (1264619146).

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

1221011204 is a wasteful number, since it uses less digits than its factorization.

1221011204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6229667 (or 6229658 counting only the distinct ones).

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

The square root of 1221011204 is about 34942.9707380469. The cubic root of 1221011204 is about 1068.8248676210.

Adding to 1221011204 its reverse (4021101221), we get a palindrome (5242112425).

The spelling of 1221011204 in words is "one billion, two hundred twenty-one million, eleven thousand, two hundred four".