7616721 has 16 divisors (see below), whose sum is σ = 11649024. Its totient is φ = 4336464.

The previous prime is 7616717. The next prime is 7616729. The reversal of 7616721 is 1276167.

It is a happy number.

It is not a de Polignac number, because 7616721 - 2² = 7616717 is a prime.

It is an Ulam number.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7616729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7570 + ... + 8516.

It is an arithmetic number, because the mean of its divisors is an integer number (728064).

Almost surely, 2^7616721 is an apocalyptic number.

It is an amenable number.

7616721 is a deficient number, since it is larger than the sum of its proper divisors (4032303).

7616721 is a wasteful number, since it uses less digits than its factorization.

7616721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340.

The product of its digits is 3528, while the sum is 30.

The square root of 7616721 is about 2759.8407562756. The cubic root of 7616721 is about 196.7535978164.

The spelling of 7616721 in words is "seven million, six hundred sixteen thousand, seven hundred twenty-one".