7132721 has 4 divisors (see below), whose sum is σ = 7203444. Its totient is φ = 7062000.

The previous prime is 7132709. The next prime is 7132751. The reversal of 7132721 is 1272317.

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 6553600 + 579121 = 2560^2 + 761^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7132721 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7132751) 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, 35210 + ... + 35411.

It is an arithmetic number, because the mean of its divisors is an integer number (1800861).

Almost surely, 2^7132721 is an apocalyptic number.

It is an amenable number.

7132721 is a deficient number, since it is larger than the sum of its proper divisors (70723).

7132721 is a wasteful number, since it uses less digits than its factorization.

7132721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70722.

The product of its digits is 588, while the sum is 23.

The square root of 7132721 is about 2670.7154472163. The cubic root of 7132721 is about 192.4945385531.

The spelling of 7132721 in words is "seven million, one hundred thirty-two thousand, seven hundred twenty-one".