3975021 has 32 divisors (see below), whose sum is σ = 6347520. Its totient is φ = 2452032.

The previous prime is 3975017. The next prime is 3975031. The reversal of 3975021 is 1205793.

3975021 = 69² + 70² + ... + 230².

It is not a de Polignac number, because 3975021 - 2² = 3975017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3975011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22891 + ... + 23063.

It is an arithmetic number, because the mean of its divisors is an integer number (198360).

Almost surely, 2^3975021 is an apocalyptic number.

It is an amenable number.

3975021 is a deficient number, since it is larger than the sum of its proper divisors (2372499).

3975021 is a wasteful number, since it uses less digits than its factorization.

3975021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 27.

The square root of 3975021 is about 1993.7454702143. The cubic root of 3975021 is about 158.4089842241.

The spelling of 3975021 in words is "three million, nine hundred seventy-five thousand, twenty-one".