7506721 has 8 divisors (see below), whose sum is σ = 7706600. Its totient is φ = 7309440.

The previous prime is 7506701. The next prime is 7506739. The reversal of 7506721 is 1276057.

It can be written as a sum of positive squares in 4 ways, for example, as 21025 + 7485696 = 145^2 + 2736^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7506721 - 2⁷ = 7506593 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7506721.

It is not an unprimeable number, because it can be changed into a prime (7506701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6085 + ... + 7213.

It is an arithmetic number, because the mean of its divisors is an integer number (963325).

Almost surely, 2^7506721 is an apocalyptic number.

It is an amenable number.

7506721 is a deficient number, since it is larger than the sum of its proper divisors (199879).

7506721 is a wasteful number, since it uses less digits than its factorization.

7506721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1299.

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 7506721 is about 2739.8395938449. The cubic root of 7506721 is about 195.8018353244.

The spelling of 7506721 in words is "seven million, five hundred six thousand, seven hundred twenty-one".