1221713609 has 8 divisors (see below), whose sum is σ = 1276336320. Its totient is φ = 1167216336.

The previous prime is 1221713599. The next prime is 1221713617. The reversal of 1221713609 is 9063171221.

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 1221713609 - 2⁴ = 1221713593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221713639) 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, 11162 + ... + 50675.

It is an arithmetic number, because the mean of its divisors is an integer number (159542040).

Almost surely, 2^1221713609 is an apocalyptic number.

It is an amenable number.

1221713609 is a deficient number, since it is larger than the sum of its proper divisors (54622711).

1221713609 is an equidigital number, since it uses as much as digits as its factorization.

1221713609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62719.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 1221713609 is about 34953.0200268875. The cubic root of 1221713609 is about 1069.0297808424.

The spelling of 1221713609 in words is "one billion, two hundred twenty-one million, seven hundred thirteen thousand, six hundred nine".