7720240 has 80 divisors (see below), whose sum is σ = 20284416. Its totient is φ = 2707200.

The previous prime is 7720211. The next prime is 7720241. The reversal of 7720240 is 420277.

7720240 is nontrivially palindromic in base 15.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (7720241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27139 + ... + 27421.

Almost surely, 2^7720240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7720240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10142208).

7720240 is an abundant number, since it is smaller than the sum of its proper divisors (12564176).

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

7720240 is a wasteful number, since it uses less digits than its factorization.

7720240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338 (or 332 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 22.

The square root of 7720240 is about 2778.5319864993. The cubic root of 7720240 is about 197.6409504971.

The spelling of 7720240 in words is "seven million, seven hundred twenty thousand, two hundred forty".