1221303997 has 8 divisors (see below), whose sum is σ = 1243844000. Its totient is φ = 1198845360.

The previous prime is 1221303973. The next prime is 1221304033. The reversal of 1221303997 is 7993031221.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1221303997 - 2¹⁹ = 1220779709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221303947) 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, 10378 + ... + 50500.

It is an arithmetic number, because the mean of its divisors is an integer number (155480500).

Almost surely, 2^1221303997 is an apocalyptic number.

It is an amenable number.

1221303997 is a deficient number, since it is larger than the sum of its proper divisors (22540003).

1221303997 is an equidigital number, since it uses as much as digits as its factorization.

1221303997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40683.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 1221303997 is about 34947.1600705980. The cubic root of 1221303997 is about 1068.9102939266.

The spelling of 1221303997 in words is "one billion, two hundred twenty-one million, three hundred three thousand, nine hundred ninety-seven".