78631000128 has 420 divisors, whose sum is σ = 248718029868. Its totient is φ = 24552253440.

The previous prime is 78631000121. The next prime is 78631000153. The reversal of 78631000128 is 82100013687.

78631000128 is a `hidden beast` number, since 7 + 8 + 631 + 0 + 0 + 0 + 12 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 44231137344 + 34399862784 = 210312^2 + 185472^2 .

It is a super-2 number, since 2×78631000128² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 78631000092 and 78631000101.

It is not an unprimeable number, because it can be changed into a prime (78631000121) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 145343538 + ... + 145344078.

Almost surely, 2^78631000128 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 78631000128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124359014934).

78631000128 is an abundant number, since it is smaller than the sum of its proper divisors (170087029740).

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

78631000128 is a wasteful number, since it uses less digits than its factorization.

78631000128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 664 (or 622 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 78631000128 in words is "seventy-eight billion, six hundred thirty-one million, one hundred twenty-eight", and thus it is an aban number.