1221743436 has 48 divisors (see below), whose sum is σ = 2954175840. Its totient is φ = 392519680.

The previous prime is 1221743423. The next prime is 1221743519. The reversal of 1221743436 is 6343471221.

It is a junction number, because it is equal to n+sod(n) for n = 1221743397 and 1221743406.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 220330 + ... + 225806.

It is an arithmetic number, because the mean of its divisors is an integer number (61545330).

Almost surely, 2^1221743436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221743436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1477087920).

1221743436 is an abundant number, since it is smaller than the sum of its proper divisors (1732432404).

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

1221743436 is a wasteful number, since it uses less digits than its factorization.

1221743436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6154 (or 6152 counting only the distinct ones).

The product of its digits is 24192, while the sum is 33.

The square root of 1221743436 is about 34953.4466969997. The cubic root of 1221743436 is about 1069.0384805604.

The spelling of 1221743436 in words is "one billion, two hundred twenty-one million, seven hundred forty-three thousand, four hundred thirty-six".