3521999 has 4 divisors (see below), whose sum is σ = 3792936. Its totient is φ = 3251064.

The previous prime is 3521977. The next prime is 3522007. The reversal of 3521999 is 9991253.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9991253 = 461 ⋅21673.

It is a cyclic number.

It is not a de Polignac number, because 3521999 - 2²⁰ = 2473423 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 (3521909) 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, 135449 + ... + 135474.

It is an arithmetic number, because the mean of its divisors is an integer number (948234).

Almost surely, 2^3521999 is an apocalyptic number.

3521999 is a deficient number, since it is larger than the sum of its proper divisors (270937).

3521999 is a wasteful number, since it uses less digits than its factorization.

3521999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270936.

The product of its digits is 21870, while the sum is 38.

The square root of 3521999 is about 1876.6989636060. The cubic root of 3521999 is about 152.1468888219.

The spelling of 3521999 in words is "three million, five hundred twenty-one thousand, nine hundred ninety-nine".