1221202021204 has 96 divisors (see below), whose sum is σ = 2489030691840. Its totient is φ = 518111424000.

The previous prime is 1221202021201. The next prime is 1221202021271. The reversal of 1221202021204 is 4021202021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221202021201) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 69906079 + ... + 69923545.

It is an arithmetic number, because the mean of its divisors is an integer number (25927403040).

Almost surely, 2^{1221202021204} is an apocalyptic number.

It is an amenable number.

1221202021204 is an abundant number, since it is smaller than the sum of its proper divisors (1267828670636).

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

1221202021204 is a wasteful number, since it uses less digits than its factorization.

1221202021204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18269 (or 18267 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 1221202021204 its reverse (4021202021221), we get a palindrome (5242404042425).

The spelling of 1221202021204 in words is "one trillion, two hundred twenty-one billion, two hundred two million, twenty-one thousand, two hundred four".