1356666689 has 4 divisors (see below), whose sum is σ = 1550476224. Its totient is φ = 1162857156.

The previous prime is 1356666677. The next prime is 1356666743. The reversal of 1356666689 is 9866666531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1356666689 - 2⁸ = 1356666433 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (1356666659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 96904757 + ... + 96904770.

It is an arithmetic number, because the mean of its divisors is an integer number (387619056).

Almost surely, 2^1356666689 is an apocalyptic number.

It is an amenable number.

1356666689 is a deficient number, since it is larger than the sum of its proper divisors (193809535).

1356666689 is an equidigital number, since it uses as much as digits as its factorization.

1356666689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193809534.

The product of its digits is 8398080, while the sum is 56.

The square root of 1356666689 is about 36832.9565606672. The cubic root of 1356666689 is about 1107.0257439787.

The spelling of 1356666689 in words is "one billion, three hundred fifty-six million, six hundred sixty-six thousand, six hundred eighty-nine".