19867405506 has 64 divisors (see below), whose sum is σ = 43961702400. Its totient is φ = 5946716160.

The previous prime is 19867405477. The next prime is 19867405513. The reversal of 19867405506 is 60550476891.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1120095 + ... + 1137693.

It is an arithmetic number, because the mean of its divisors is an integer number (686901600).

Almost surely, 2^19867405506 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19867405506, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21980851200).

19867405506 is an abundant number, since it is smaller than the sum of its proper divisors (24094296894).

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

19867405506 is a wasteful number, since it uses less digits than its factorization.

19867405506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18011.

The product of its (nonzero) digits is 1814400, while the sum is 51.

The spelling of 19867405506 in words is "nineteen billion, eight hundred sixty-seven million, four hundred five thousand, five hundred six".