19987467864 has 64 divisors (see below), whose sum is σ = 61499907840. Its totient is φ = 5271419520.

The previous prime is 19987467859. The next prime is 19987467869. The reversal of 19987467864 is 46876478991.

It is an interprime number because it is at equal distance from previous prime (19987467859) and next prime (19987467869).

It is a super-2 number, since 2×19987467864² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19987467869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4573702 + ... + 4578069.

It is an arithmetic number, because the mean of its divisors is an integer number (960936060).

Almost surely, 2^19987467864 is an apocalyptic number.

19987467864 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

19987467864 is an abundant number, since it is smaller than the sum of its proper divisors (41512439976).

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

19987467864 is a wasteful number, since it uses less digits than its factorization.

19987467864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9151800 (or 9151796 counting only the distinct ones).

The product of its digits is 146313216, while the sum is 69.

The spelling of 19987467864 in words is "nineteen billion, nine hundred eighty-seven million, four hundred sixty-seven thousand, eight hundred sixty-four".