3506021 has 4 divisors (see below), whose sum is σ = 3509772. Its totient is φ = 3502272.

The previous prime is 3505991. The next prime is 3506023. The reversal of 3506021 is 1206053.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1240996 + 2265025 = 1114^2 + 1505^2 .

It is a cyclic number.

It is not a de Polignac number, because 3506021 - 2¹⁰ = 3504997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3506023) 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, 791 + ... + 2763.

It is an arithmetic number, because the mean of its divisors is an integer number (877443).

Almost surely, 2^3506021 is an apocalyptic number.

It is an amenable number.

3506021 is a deficient number, since it is larger than the sum of its proper divisors (3751).

3506021 is a wasteful number, since it uses less digits than its factorization.

3506021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3750.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 3506021 is about 1872.4371818568. The cubic root of 3506021 is about 151.9164620606.

Subtracting from 3506021 its reverse (1206053), we obtain a cube (2299968 = 132³).

The spelling of 3506021 in words is "three million, five hundred six thousand, twenty-one".