13121986500 has 384 divisors, whose sum is σ = 48843325440. Its totient is φ = 2979504000.

The previous prime is 13121986487. The next prime is 13121986517. The reversal of 13121986500 is 568912131.

13121986500 is a `hidden beast` number, since 131 + 2 + 19 + 8 + 6 + 500 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 18049137 + ... + 18049863.

It is an arithmetic number, because the mean of its divisors is an integer number (127196160).

Almost surely, 2^13121986500 is an apocalyptic number.

13121986500 is a gapful number since it is divisible by the number (10) 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 13121986500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24421662720).

13121986500 is an abundant number, since it is smaller than the sum of its proper divisors (35721338940).

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

13121986500 is a wasteful number, since it uses less digits than its factorization.

13121986500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 953 (or 935 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 13121986500 in words is "thirteen billion, one hundred twenty-one million, nine hundred eighty-six thousand, five hundred".