7778628 has 72 divisors (see below), whose sum is σ = 23115456. Its totient is φ = 2174400.

The previous prime is 7778627. The next prime is 7778629. The reversal of 7778628 is 8268777.

It is an interprime number because it is at equal distance from previous prime (7778627) and next prime (7778629).

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7778627) 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 23 ways as a sum of consecutive naturals, for example, 4393 + ... + 5903.

It is an arithmetic number, because the mean of its divisors is an integer number (321048).

Almost surely, 2^7778628 is an apocalyptic number.

7778628 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7778628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11557728).

7778628 is an abundant number, since it is smaller than the sum of its proper divisors (15336828).

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

7778628 is a wasteful number, since it uses less digits than its factorization.

7778628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1545 (or 1540 counting only the distinct ones).

The product of its digits is 263424, while the sum is 45.

The square root of 7778628 is about 2789.0191824367. The cubic root of 7778628 is about 198.1379510022.

The spelling of 7778628 in words is "seven million, seven hundred seventy-eight thousand, six hundred twenty-eight".