19813866072 has 128 divisors (see below), whose sum is σ = 66508162560. Its totient is φ = 4750571520.

The previous prime is 19813866067. The next prime is 19813866073. The reversal of 19813866072 is 27066831891.

It is a super-4 number, since 4×19813866072⁴ (a number of 42 digits) contains 4444 as substring. Note that it is a super-d number also for d = 3.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19813866073) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 388353 + ... + 436400.

It is an arithmetic number, because the mean of its divisors is an integer number (519595020).

Almost surely, 2^19813866072 is an apocalyptic number.

19813866072 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

19813866072 is an abundant number, since it is smaller than the sum of its proper divisors (46694296488).

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

19813866072 is a wasteful number, since it uses less digits than its factorization.

19813866072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 824793 (or 824789 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 51.

The spelling of 19813866072 in words is "nineteen billion, eight hundred thirteen million, eight hundred sixty-six thousand, seventy-two".