7516221 has 4 divisors (see below), whose sum is σ = 10021632. Its totient is φ = 5010812.

The previous prime is 7516213. The next prime is 7516247. The reversal of 7516221 is 1226157.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1226157 = 3 ⋅408719.

It is a cyclic number.

It is not a de Polignac number, because 7516221 - 2³ = 7516213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 7516191 and 7516200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7516211) 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, 1252701 + ... + 1252706.

It is an arithmetic number, because the mean of its divisors is an integer number (2505408).

Almost surely, 2^7516221 is an apocalyptic number.

It is an amenable number.

7516221 is a deficient number, since it is larger than the sum of its proper divisors (2505411).

7516221 is a wasteful number, since it uses less digits than its factorization.

7516221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2505410.

The product of its digits is 840, while the sum is 24.

The square root of 7516221 is about 2741.5727238211. The cubic root of 7516221 is about 195.8843983728.

Subtracting from 7516221 its reverse (1226157), we obtain a square (6290064 = 2508²).

The spelling of 7516221 in words is "seven million, five hundred sixteen thousand, two hundred twenty-one".