7072721 has 4 divisors (see below), whose sum is σ = 7178352. Its totient is φ = 6967092.

The previous prime is 7072699. The next prime is 7072771. The reversal of 7072721 is 1272707.

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: 1272707 = 167 ⋅7621.

It is a cyclic number.

It is not a de Polignac number, because 7072721 - 2⁶ = 7072657 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7072771) 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, 52715 + ... + 52848.

It is an arithmetic number, because the mean of its divisors is an integer number (1794588).

Almost surely, 2^7072721 is an apocalyptic number.

It is an amenable number.

7072721 is a deficient number, since it is larger than the sum of its proper divisors (105631).

7072721 is a wasteful number, since it uses less digits than its factorization.

7072721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105630.

The product of its (nonzero) digits is 1372, while the sum is 26.

The square root of 7072721 is about 2659.4587795264. The cubic root of 7072721 is about 191.9532673444.

The spelling of 7072721 in words is "seven million, seventy-two thousand, seven hundred twenty-one".