4390521 has 4 divisors (see below), whose sum is σ = 5854032. Its totient is φ = 2927012.

The previous prime is 4390489. The next prime is 4390523. The reversal of 4390521 is 1250934.

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 4390521 - 2⁵ = 4390489 is a prime.

It is an Ulam number.

It is a D-number.

It is a Curzon number.

It is a nialpdrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 4390491 and 4390500.

It is not an unprimeable number, because it can be changed into a prime (4390523) 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, 731751 + ... + 731756.

It is an arithmetic number, because the mean of its divisors is an integer number (1463508).

Almost surely, 2^4390521 is an apocalyptic number.

It is an amenable number.

4390521 is a deficient number, since it is larger than the sum of its proper divisors (1463511).

4390521 is a wasteful number, since it uses less digits than its factorization.

4390521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1463510.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 4390521 is about 2095.3570101536. The cubic root of 4390521 is about 163.7464976039.

The spelling of 4390521 in words is "four million, three hundred ninety thousand, five hundred twenty-one".