7720345 has 8 divisors (see below), whose sum is σ = 9281160. Its totient is φ = 6165120.

The previous prime is 7720337. The next prime is 7720357. The reversal of 7720345 is 5430277.

It can be written as a sum of positive squares in 4 ways, for example, as 687241 + 7033104 = 829^2 + 2652^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 7720345 - 2³ = 7720337 is a prime.

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2791 + ... + 4819.

It is an arithmetic number, because the mean of its divisors is an integer number (1160145).

Almost surely, 2^7720345 is an apocalyptic number.

It is an amenable number.

7720345 is a deficient number, since it is larger than the sum of its proper divisors (1560815).

7720345 is a wasteful number, since it uses less digits than its factorization.

7720345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2795.

The product of its (nonzero) digits is 5880, while the sum is 28.

The square root of 7720345 is about 2778.5508813049. The cubic root of 7720345 is about 197.6418465057.

The spelling of 7720345 in words is "seven million, seven hundred twenty thousand, three hundred forty-five".