1221404036 has 6 divisors (see below), whose sum is σ = 2137457070. Its totient is φ = 610702016.

The previous prime is 1221404033. The next prime is 1221404057. The reversal of 1221404036 is 6304041221.

It can be written as a sum of positive squares in only one way, i.e., 1135285636 + 86118400 = 33694^2 + 9280^2 .

It is not an unprimeable number, because it can be changed into a prime (1221404033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152675501 + ... + 152675508.

It is an arithmetic number, because the mean of its divisors is an integer number (356242845).

Almost surely, 2^1221404036 is an apocalyptic number.

It is an amenable number.

1221404036 is a deficient number, since it is larger than the sum of its proper divisors (916053034).

1221404036 is a wasteful number, since it uses less digits than its factorization.

1221404036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305351013 (or 305351011 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 1221404036 is about 34948.5913306960. The cubic root of 1221404036 is about 1068.9394785242.

Adding to 1221404036 its reverse (6304041221), we get a palindrome (7525445257).

The spelling of 1221404036 in words is "one billion, two hundred twenty-one million, four hundred four thousand, thirty-six".