4021257 has 4 divisors (see below), whose sum is σ = 5361680. Its totient is φ = 2680836.

The previous prime is 4021249. The next prime is 4021261. The reversal of 4021257 is 7521204.

4021257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is not a de Polignac number, because 4021257 - 2³ = 4021249 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4021207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 670207 + ... + 670212.

It is an arithmetic number, because the mean of its divisors is an integer number (1340420).

Almost surely, 2^4021257 is an apocalyptic number.

It is an amenable number.

4021257 is a deficient number, since it is larger than the sum of its proper divisors (1340423).

4021257 is a wasteful number, since it uses less digits than its factorization.

4021257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340422.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 4021257 is about 2005.3072083848. The cubic root of 4021257 is about 159.0208034170.

It can be divided in two parts, 4021 and 257, that added together give a triangular number (4278 = T₉₂).

The spelling of 4021257 in words is "four million, twenty-one thousand, two hundred fifty-seven".