1320011021 has 4 divisors (see below), whose sum is σ = 1508584032. Its totient is φ = 1131438012.

The previous prime is 1320011003. The next prime is 1320011083. The reversal of 1320011021 is 1201100231.

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: 1201100231 = 1741 ⋅689891.

It is a cyclic number.

It is not a de Polignac number, because 1320011021 - 2³⁰ = 246269197 is a prime.

It is a super-2 number, since 2×1320011021² = 3484858191122924882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1320010993 and 1320011011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320011621) 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, 94286495 + ... + 94286508.

It is an arithmetic number, because the mean of its divisors is an integer number (377146008).

Almost surely, 2^1320011021 is an apocalyptic number.

It is an amenable number.

1320011021 is a deficient number, since it is larger than the sum of its proper divisors (188573011).

1320011021 is an equidigital number, since it uses as much as digits as its factorization.

1320011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188573010.

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

The square root of 1320011021 is about 36331.9559203740. The cubic root of 1320011021 is about 1096.9643634100.

Adding to 1320011021 its reverse (1201100231), we get a palindrome (2521111252).

The spelling of 1320011021 in words is "one billion, three hundred twenty million, eleven thousand, twenty-one".