19918692864 has 360 divisors, whose sum is σ = 70407033840. Its totient is φ = 5390364672.

The previous prime is 19918692851. The next prime is 19918692877. The reversal of 19918692864 is 46829681991.

It is an interprime number because it is at equal distance from previous prime (19918692851) and next prime (19918692877).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4287727 + ... + 4292369.

It is an arithmetic number, because the mean of its divisors is an integer number (195575094).

Almost surely, 2^19918692864 is an apocalyptic number.

19918692864 is a gapful number since it is divisible by the number (14) 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 19918692864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35203516920).

19918692864 is an abundant number, since it is smaller than the sum of its proper divisors (50488340976).

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

19918692864 is a wasteful number, since it uses less digits than its factorization.

19918692864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4700 (or 4674 counting only the distinct ones).

The product of its digits is 13436928, while the sum is 63.

The spelling of 19918692864 in words is "nineteen billion, nine hundred eighteen million, six hundred ninety-two thousand, eight hundred sixty-four".