79661449728 has 720 divisors, whose sum is σ = 282719717280. Its totient is φ = 22323216384.

The previous prime is 79661449711. The next prime is 79661449729. The reversal of 79661449728 is 82794416697.

79661449728 is a `hidden beast` number, since 7 + 9 + 6 + 614 + 4 + 9 + 7 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (79661449729) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 445035943 + ... + 445036121.

It is an arithmetic number, because the mean of its divisors is an integer number (392666274).

Almost surely, 2^79661449728 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 79661449728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141359858640).

79661449728 is an abundant number, since it is smaller than the sum of its proper divisors (203058267552).

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

79661449728 is an equidigital number, since it uses as much as digits as its factorization.

79661449728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299 (or 264 counting only the distinct ones).

The product of its digits is 36578304, while the sum is 63.

The spelling of 79661449728 in words is "seventy-nine billion, six hundred sixty-one million, four hundred forty-nine thousand, seven hundred twenty-eight".