7501721 has 8 divisors (see below), whose sum is σ = 7833600. Its totient is φ = 7175520.

The previous prime is 7501693. The next prime is 7501723. The reversal of 7501721 is 1271057.

It is a happy number.

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 7501721 - 2¹⁴ = 7485337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7501723) 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, 1400 + ... + 4118.

It is an arithmetic number, because the mean of its divisors is an integer number (979200).

Almost surely, 2^7501721 is an apocalyptic number.

It is an amenable number.

7501721 is a deficient number, since it is larger than the sum of its proper divisors (331879).

7501721 is a wasteful number, since it uses less digits than its factorization.

7501721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2839.

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 7501721 is about 2738.9269796765. The cubic root of 7501721 is about 195.7583531072.

Adding to 7501721 its reverse (1271057), we get a palindrome (8772778).

The spelling of 7501721 in words is "seven million, five hundred one thousand, seven hundred twenty-one".