7720668 has 18 divisors (see below), whose sum is σ = 19516224. Its totient is φ = 2573544.

The previous prime is 7720667. The next prime is 7720673. The reversal of 7720668 is 8660277.

7720668 = T₁₅₂ + T₁₅₃ + ... + T₃₆₇.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 214463 = 7720668 / (7 + 7 + 2 + 0 + 6 + 6 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7720667) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 107196 + ... + 107267.

Almost surely, 2^7720668 is an apocalyptic number.

It is an amenable number.

7720668 is an abundant number, since it is smaller than the sum of its proper divisors (11795556).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7720668 is a wasteful number, since it uses less digits than its factorization.

7720668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214473 (or 214468 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 7720668 is about 2778.6090045201. The cubic root of 7720668 is about 197.6446027481.

The spelling of 7720668 in words is "seven million, seven hundred twenty thousand, six hundred sixty-eight".