19867436420 has 144 divisors (see below), whose sum is σ = 46538864064. Its totient is φ = 7081651200.

The previous prime is 19867436357. The next prime is 19867436437. The reversal of 19867436420 is 2463476891.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 57254687 + ... + 57255033.

It is an arithmetic number, because the mean of its divisors is an integer number (323186556).

Almost surely, 2^19867436420 is an apocalyptic number.

19867436420 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 19867436420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23269432032).

19867436420 is an abundant number, since it is smaller than the sum of its proper divisors (26671427644).

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

19867436420 is a wasteful number, since it uses less digits than its factorization.

19867436420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582 (or 539 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 50.

The spelling of 19867436420 in words is "nineteen billion, eight hundred sixty-seven million, four hundred thirty-six thousand, four hundred twenty".