1221506366 has 8 divisors (see below), whose sum is σ = 1832407920. Its totient is φ = 610703728.

The previous prime is 1221506357. The next prime is 1221506387. The reversal of 1221506366 is 6636051221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34970 + ... + 60546.

It is an arithmetic number, because the mean of its divisors is an integer number (229050990).

Almost surely, 2^1221506366 is an apocalyptic number.

1221506366 is a deficient number, since it is larger than the sum of its proper divisors (610901554).

1221506366 is a wasteful number, since it uses less digits than its factorization.

1221506366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49458.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 1221506366 is about 34950.0553075385. The cubic root of 1221506366 is about 1068.9693298317.

Adding to 1221506366 its reverse (6636051221), we get a palindrome (7857557587).

The spelling of 1221506366 in words is "one billion, two hundred twenty-one million, five hundred six thousand, three hundred sixty-six".