4157021 has 4 divisors (see below), whose sum is σ = 4534944. Its totient is φ = 3779100.

The previous prime is 4157011. The next prime is 4157053. The reversal of 4157021 is 1207514.

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 a cyclic number.

It is not a de Polignac number, because 4157021 - 2¹⁰ = 4155997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 4156984 and 4157002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4157011) 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, 188945 + ... + 188966.

It is an arithmetic number, because the mean of its divisors is an integer number (1133736).

Almost surely, 2^4157021 is an apocalyptic number.

It is an amenable number.

4157021 is a deficient number, since it is larger than the sum of its proper divisors (377923).

4157021 is a wasteful number, since it uses less digits than its factorization.

4157021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377922.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 4157021 is about 2038.8773871913. The cubic root of 4157021 is about 160.7906309773.

The spelling of 4157021 in words is "four million, one hundred fifty-seven thousand, twenty-one".