129799696428 has 240 divisors, whose sum is σ = 352848545280. Its totient is φ = 41584772736.

The previous prime is 129799696417. The next prime is 129799696447. The reversal of 129799696428 is 824696997921.

129799696428 is a `hidden beast` number, since 1 + 29 + 7 + 9 + 96 + 96 + 428 = 666.

It is a super-2 number, since 2×129799696428² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 221123551 + ... + 221124137.

It is an arithmetic number, because the mean of its divisors is an integer number (1470202272).

Almost surely, 2^129799696428 is an apocalyptic number.

129799696428 is a gapful number since it is divisible by the number (18) 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 129799696428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (176424272640).

129799696428 is an abundant number, since it is smaller than the sum of its proper divisors (223048848852).

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

129799696428 is a wasteful number, since it uses less digits than its factorization.

129799696428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 898 (or 887 counting only the distinct ones).

The product of its digits is 211631616, while the sum is 72.

The spelling of 129799696428 in words is "one hundred twenty-nine billion, seven hundred ninety-nine million, six hundred ninety-six thousand, four hundred twenty-eight".