1320666533 has 4 divisors (see below), whose sum is σ = 1320875340. Its totient is φ = 1320457728.

The previous prime is 1320666521. The next prime is 1320666559. The reversal of 1320666533 is 3356660231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3356660231 = 73 ⋅45981647.

It can be written as a sum of positive squares in 2 ways, for example, as 780475969 + 540190564 = 27937^2 + 23242^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320666533 - 2⁶ = 1320666469 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1320666493 and 1320666502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320666733) 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, 94610 + ... + 107667.

It is an arithmetic number, because the mean of its divisors is an integer number (330218835).

Almost surely, 2^1320666533 is an apocalyptic number.

It is an amenable number.

1320666533 is a deficient number, since it is larger than the sum of its proper divisors (208807).

1320666533 is an equidigital number, since it uses as much as digits as its factorization.

1320666533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208806.

The product of its (nonzero) digits is 58320, while the sum is 35.

The square root of 1320666533 is about 36340.9759500209. The cubic root of 1320666533 is about 1097.1459160121.

The spelling of 1320666533 in words is "one billion, three hundred twenty million, six hundred sixty-six thousand, five hundred thirty-three".