19894242816 has 480 divisors, whose sum is σ = 69493552128. Its totient is φ = 5563883520.

The previous prime is 19894242803. The next prime is 19894242829. The reversal of 19894242816 is 61824249891.

It is a happy number.

19894242816 is a `hidden beast` number, since 198 + 9 + 424 + 28 + 1 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (19894242803) and next prime (19894242829).

It is a Harshad number since it is a multiple of its sum of digits (54).

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

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 46158121 + ... + 46158551.

Almost surely, 2^19894242816 is an apocalyptic number.

19894242816 is a gapful number since it is divisible by the number (16) 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 19894242816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34746776064).

19894242816 is an abundant number, since it is smaller than the sum of its proper divisors (49599309312).

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

19894242816 is an frugal number, since it uses more digits than its factorization.

19894242816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524 (or 496 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 54.

The spelling of 19894242816 in words is "nineteen billion, eight hundred ninety-four million, two hundred forty-two thousand, eight hundred sixteen".