1221855052 has 24 divisors (see below), whose sum is σ = 2382266880. Its totient is φ = 543570960.

The previous prime is 1221855043. The next prime is 1221855053. The reversal of 1221855052 is 2505581221.

It is not an unprimeable number, because it can be changed into a prime (1221855053) 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, 293352 + ... + 297487.

It is an arithmetic number, because the mean of its divisors is an integer number (99261120).

Almost surely, 2^1221855052 is an apocalyptic number.

It is an amenable number.

1221855052 is a deficient number, since it is larger than the sum of its proper divisors (1160411828).

1221855052 is a wasteful number, since it uses less digits than its factorization.

1221855052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 590901 (or 590899 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 31.

The square root of 1221855052 is about 34955.0432984999. The cubic root of 1221855052 is about 1069.0710346309.

The spelling of 1221855052 in words is "one billion, two hundred twenty-one million, eight hundred fifty-five thousand, fifty-two".