7681239720 has 672 divisors, whose sum is σ = 32655692160. Its totient is φ = 1590969600.

The previous prime is 7681239719. The next prime is 7681239739. The reversal of 7681239720 is 279321867.

It is a super-2 number, since 2×7681239720² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 167 ways as a sum of consecutive naturals, for example, 24698365 + ... + 24698675.

It is an arithmetic number, because the mean of its divisors is an integer number (48594780).

Almost surely, 2^7681239720 is an apocalyptic number.

7681239720 is a gapful number since it is divisible by the number (70) 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 7681239720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16327846080).

7681239720 is an abundant number, since it is smaller than the sum of its proper divisors (24974452440).

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

7681239720 is a wasteful number, since it uses less digits than its factorization.

7681239720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369 (or 339 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The square root of 7681239720 is about 87642.6820675862. The cubic root of 7681239720 is about 1973.0758139066.

The spelling of 7681239720 in words is "seven billion, six hundred eighty-one million, two hundred thirty-nine thousand, seven hundred twenty".