2620021021 has 4 divisors (see below), whose sum is σ = 2620225152. Its totient is φ = 2619816892.

The previous prime is 2620021007. The next prime is 2620021039. The reversal of 2620021021 is 1201200262.

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: 1201200262 = 2 ⋅600600131.

It is a cyclic number.

It is not a de Polignac number, because 2620021021 - 2⁵ = 2620020989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2620020986 and 2620021004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2620321021) 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, 81421 + ... + 108946.

It is an arithmetic number, because the mean of its divisors is an integer number (655056288).

Almost surely, 2^2620021021 is an apocalyptic number.

It is an amenable number.

2620021021 is a deficient number, since it is larger than the sum of its proper divisors (204131).

2620021021 is a wasteful number, since it uses less digits than its factorization.

2620021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204130.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 2620021021 is about 51186.1409074761. The cubic root of 2620021021 is about 1378.5893694795.

Adding to 2620021021 its reverse (1201200262), we get a palindrome (3821221283).

The spelling of 2620021021 in words is "two billion, six hundred twenty million, twenty-one thousand, twenty-one".