7151521 has 4 divisors (see below), whose sum is σ = 7701652. Its totient is φ = 6601392.

The previous prime is 7151503. The next prime is 7151531. The reversal of 7151521 is 1251517.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1251517 = 71 ⋅17627.

It can be written as a sum of positive squares in 2 ways, for example, as 3294225 + 3857296 = 1815^2 + 1964^2 .

It is a cyclic number.

It is not a de Polignac number, because 7151521 - 2⁵ = 7151489 is a prime.

It is a super-2 number, since 2×7151521² = 102288505226882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7151492 and 7151501.

It is not an unprimeable number, because it can be changed into a prime (7151531) 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, 275046 + ... + 275071.

It is an arithmetic number, because the mean of its divisors is an integer number (1925413).

Almost surely, 2^7151521 is an apocalyptic number.

It is an amenable number.

7151521 is a deficient number, since it is larger than the sum of its proper divisors (550131).

7151521 is a wasteful number, since it uses less digits than its factorization.

7151521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550130.

The product of its digits is 350, while the sum is 22.

The square root of 7151521 is about 2674.2327871747. The cubic root of 7151521 is about 192.6635120524.

The spelling of 7151521 in words is "seven million, one hundred fifty-one thousand, five hundred twenty-one".