1320101021 has 4 divisors (see below), whose sum is σ = 1325916672. Its totient is φ = 1314285372.

The previous prime is 1320101009. The next prime is 1320101047. The reversal of 1320101021 is 1201010231.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1201010231 = 1039 ⋅1155929.

It is a cyclic number.

It is not a de Polignac number, because 1320101021 - 2¹⁴ = 1320084637 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 = 1320100993 and 1320101011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320101521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2907485 + ... + 2907938.

It is an arithmetic number, because the mean of its divisors is an integer number (331479168).

Almost surely, 2^1320101021 is an apocalyptic number.

It is an amenable number.

1320101021 is a deficient number, since it is larger than the sum of its proper divisors (5815651).

1320101021 is an equidigital number, since it uses as much as digits as its factorization.

1320101021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5815650.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 1320101021 is about 36333.1944783279. The cubic root of 1320101021 is about 1096.9892936435.

Adding to 1320101021 its reverse (1201010231), we get a palindrome (2521111252).

The spelling of 1320101021 in words is "one billion, three hundred twenty million, one hundred one thousand, twenty-one".