19857513520 has 120 divisors (see below), whose sum is σ = 51157480176. Its totient is φ = 7161283584.

The previous prime is 19857513499. The next prime is 19857513521. The reversal of 19857513520 is 2531575891.

It is not an unprimeable number, because it can be changed into a prime (19857513521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 564282 + ... + 598438.

Almost surely, 2^19857513520 is an apocalyptic number.

19857513520 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 19857513520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25578740088).

19857513520 is an abundant number, since it is smaller than the sum of its proper divisors (31299966656).

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

19857513520 is a wasteful number, since it uses less digits than its factorization.

19857513520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34239 (or 34220 counting only the distinct ones).

The product of its (nonzero) digits is 378000, while the sum is 46.

The spelling of 19857513520 in words is "nineteen billion, eight hundred fifty-seven million, five hundred thirteen thousand, five hundred twenty".