4257021 has 8 divisors (see below), whose sum is σ = 6009984. Its totient is φ = 2671040.

The previous prime is 4257017. The next prime is 4257023. The reversal of 4257021 is 1207524.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 4257021 - 2² = 4257017 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4257023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41685 + ... + 41786.

It is an arithmetic number, because the mean of its divisors is an integer number (751248).

Almost surely, 2^4257021 is an apocalyptic number.

It is an amenable number.

4257021 is a deficient number, since it is larger than the sum of its proper divisors (1752963).

4257021 is a wasteful number, since it uses less digits than its factorization.

4257021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83491.

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

The square root of 4257021 is about 2063.2549527385. The cubic root of 4257021 is about 162.0697383025.

The spelling of 4257021 in words is "four million, two hundred fifty-seven thousand, twenty-one".