1221053204 has 24 divisors (see below), whose sum is σ = 2450078400. Its totient is φ = 521600256.

The previous prime is 1221053201. The next prime is 1221053209. The reversal of 1221053204 is 4023501221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221053201) 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, 62429 + ... + 79620.

It is an arithmetic number, because the mean of its divisors is an integer number (102086600).

Almost surely, 2^1221053204 is an apocalyptic number.

1221053204 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1221053204 is an abundant number, since it is smaller than the sum of its proper divisors (1229025196).

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

1221053204 is a wasteful number, since it uses less digits than its factorization.

1221053204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142367 (or 142365 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1221053204 is about 34943.5717121190. The cubic root of 1221053204 is about 1068.8371225262.

Adding to 1221053204 its reverse (4023501221), we get a palindrome (5244554425).

The spelling of 1221053204 in words is "one billion, two hundred twenty-one million, fifty-three thousand, two hundred four".