4145821 has 4 divisors (see below), whose sum is σ = 4154272. Its totient is φ = 4137372.

The previous prime is 4145809. The next prime is 4145837. The reversal of 4145821 is 1285414.

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 4145821 - 2⁷ = 4145693 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 (4145851) 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 3 ways as a sum of consecutive naturals, for example, 3441 + ... + 4486.

It is an arithmetic number, because the mean of its divisors is an integer number (1038568).

Almost surely, 2^4145821 is an apocalyptic number.

It is an amenable number.

4145821 is a deficient number, since it is larger than the sum of its proper divisors (8451).

4145821 is an equidigital number, since it uses as much as digits as its factorization.

4145821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8450.

The product of its digits is 1280, while the sum is 25.

The square root of 4145821 is about 2036.1289251911. The cubic root of 4145821 is about 160.6460984060.

The spelling of 4145821 in words is "four million, one hundred forty-five thousand, eight hundred twenty-one".