2851021 has 4 divisors (see below), whose sum is σ = 2855200. Its totient is φ = 2846844.

The previous prime is 2851001. The next prime is 2851049. The reversal of 2851021 is 1201582.

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: 1201582 = 2 ⋅600791.

It is a cyclic number.

It is not a de Polignac number, because 2851021 - 2⁵ = 2850989 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2851021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2851001) 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, 801 + ... + 2518.

It is an arithmetic number, because the mean of its divisors is an integer number (713800).

2^2851021 is an apocalyptic number.

It is an amenable number.

2851021 is a deficient number, since it is larger than the sum of its proper divisors (4179).

2851021 is an equidigital number, since it uses as much as digits as its factorization.

2851021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4178.

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 2851021 is about 1688.4966686375. The cubic root of 2851021 is about 141.7969225674.

The spelling of 2851021 in words is "two million, eight hundred fifty-one thousand, twenty-one".