7542421 has 4 divisors (see below), whose sum is σ = 7559244. Its totient is φ = 7525600.

The previous prime is 7542389. The next prime is 7542439. The reversal of 7542421 is 1242457.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2640625 + 4901796 = 1625^2 + 2214^2 .

It is a cyclic number.

It is not a de Polignac number, because 7542421 - 2⁵ = 7542389 is a prime.

It is a super-2 number, since 2×7542421² = 113776229082482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7542461) 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, 7720 + ... + 8641.

It is an arithmetic number, because the mean of its divisors is an integer number (1889811).

Almost surely, 2^7542421 is an apocalyptic number.

It is an amenable number.

7542421 is a deficient number, since it is larger than the sum of its proper divisors (16823).

7542421 is a wasteful number, since it uses less digits than its factorization.

7542421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16822.

The product of its digits is 2240, while the sum is 25.

The square root of 7542421 is about 2746.3468462669. The cubic root of 7542421 is about 196.1117386602. Note that the first 3 decimals are identical.

Adding to 7542421 its reverse (1242457), we get a palindrome (8784878).

The spelling of 7542421 in words is "seven million, five hundred forty-two thousand, four hundred twenty-one".