7528421 has 4 divisors (see below), whose sum is σ = 7613100. Its totient is φ = 7443744.

The previous prime is 7528403. The next prime is 7528453. The reversal of 7528421 is 1248257.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1248257 = 103 ⋅12119.

It can be written as a sum of positive squares in 2 ways, for example, as 3960100 + 3568321 = 1990^2 + 1889^2 .

It is a cyclic number.

It is not a de Polignac number, because 7528421 - 2⁶ = 7528357 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 (7528471) 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, 42206 + ... + 42383.

It is an arithmetic number, because the mean of its divisors is an integer number (1903275).

Almost surely, 2^7528421 is an apocalyptic number.

It is an amenable number.

7528421 is a deficient number, since it is larger than the sum of its proper divisors (84679).

7528421 is an equidigital number, since it uses as much as digits as its factorization.

7528421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84678.

The product of its digits is 4480, while the sum is 29.

The square root of 7528421 is about 2743.7968219240. The cubic root of 7528421 is about 195.9903247341.

The spelling of 7528421 in words is "seven million, five hundred twenty-eight thousand, four hundred twenty-one".