7977529728 has 512 divisors, whose sum is σ = 28377216000. Its totient is φ = 2158313472.

The previous prime is 7977529727. The next prime is 7977529741. The reversal of 7977529728 is 8279257797.

It is a super-2 number, since 2×7977529728² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (63) 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 (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7977529723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 58230076 + ... + 58230212.

It is an arithmetic number, because the mean of its divisors is an integer number (55424250).

Almost surely, 2^7977529728 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 7977529728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14188608000).

7977529728 is an abundant number, since it is smaller than the sum of its proper divisors (20399686272).

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

7977529728 is a wasteful number, since it uses less digits than its factorization.

7977529728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279 (or 261 counting only the distinct ones).

The product of its digits is 31116960, while the sum is 63.

The square root of 7977529728 is about 89317.0181320447. The cubic root of 7977529728 is about 1998.1257214219.

The spelling of 7977529728 in words is "seven billion, nine hundred seventy-seven million, five hundred twenty-nine thousand, seven hundred twenty-eight".