1221662003 has 4 divisors (see below), whose sum is σ = 1222086600. Its totient is φ = 1221237408.

The previous prime is 1221661993. The next prime is 1221662009. The reversal of 1221662003 is 3002661221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3002661221 = 7 ⋅428951603.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221662003 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221662003.

It is not an unprimeable number, because it can be changed into a prime (1221662009) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 207953 + ... + 213746.

It is an arithmetic number, because the mean of its divisors is an integer number (305521650).

Almost surely, 2^1221662003 is an apocalyptic number.

1221662003 is a deficient number, since it is larger than the sum of its proper divisors (424597).

1221662003 is an equidigital number, since it uses as much as digits as its factorization.

1221662003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424596.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 1221662003 is about 34952.2817996193. The cubic root of 1221662003 is about 1069.0147284528.

The spelling of 1221662003 in words is "one billion, two hundred twenty-one million, six hundred sixty-two thousand, three".