9720428129100 has 216 divisors, whose sum is σ = 32930310467600. Its totient is φ = 2384081994240.

The previous prime is 9720428129039. The next prime is 9720428129123. The reversal of 9720428129100 is 19218240279.

9720428129100 is a `hidden beast` number, since 97 + 2 + 0 + 428 + 129 + 10 + 0 = 666.

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 (23) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1741251 + ... + 4740549.

Almost surely, 2^{9720428129100} is an apocalyptic number.

9720428129100 is a gapful number since it is divisible by the number (90) 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 9720428129100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16465155233800).

9720428129100 is an abundant number, since it is smaller than the sum of its proper divisors (23209882338500).

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

9720428129100 is a wasteful number, since it uses less digits than its factorization.

9720428129100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2999609 (or 2999599 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The spelling of 9720428129100 in words is "nine trillion, seven hundred twenty billion, four hundred twenty-eight million, one hundred twenty-nine thousand, one hundred".