7620904721 has 4 divisors (see below), whose sum is σ = 8069193252. Its totient is φ = 7172616192.

The previous prime is 7620904703. The next prime is 7620904741. The reversal of 7620904721 is 1274090267.

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 6911428225 + 709476496 = 83135^2 + 26636^2 .

It is a cyclic number.

It is not a de Polignac number, because 7620904721 - 2⁶ = 7620904657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7620904741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 224144240 + ... + 224144273.

It is an arithmetic number, because the mean of its divisors is an integer number (2017298313).

Almost surely, 2^7620904721 is an apocalyptic number.

It is an amenable number.

7620904721 is a deficient number, since it is larger than the sum of its proper divisors (448288531).

7620904721 is a wasteful number, since it uses less digits than its factorization.

7620904721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448288530.

The product of its (nonzero) digits is 42336, while the sum is 38.

The square root of 7620904721 is about 87297.7933340815. The cubic root of 7620904721 is about 1967.8961556770.

Adding to 7620904721 its reverse (1274090267), we get a palindrome (8894994988).

The spelling of 7620904721 in words is "seven billion, six hundred twenty million, nine hundred four thousand, seven hundred twenty-one".