7721888 has 48 divisors (see below), whose sum is σ = 16125480. Its totient is φ = 3634176.

The previous prime is 7721873. The next prime is 7721891. The reversal of 7721888 is 8881277.

It can be written as a sum of positive squares in 4 ways, for example, as 6697744 + 1024144 = 2588^2 + 1012^2 .

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, 49106 + ... + 49262.

Almost surely, 2^7721888 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 7721888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8062740).

7721888 is an abundant number, since it is smaller than the sum of its proper divisors (8403592).

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

7721888 is a wasteful number, since it uses less digits than its factorization.

7721888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 241 counting only the distinct ones).

The product of its digits is 50176, while the sum is 41.

The square root of 7721888 is about 2778.8285301544. The cubic root of 7721888 is about 197.6550126295.

The spelling of 7721888 in words is "seven million, seven hundred twenty-one thousand, eight hundred eighty-eight".