1938198816 has 144 divisors (see below), whose sum is σ = 5849625600. Its totient is φ = 607025664.

The previous prime is 1938198803. The next prime is 1938198971. The reversal of 1938198816 is 6188918391.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×1938198816² = 7513229300687603712, which contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 693550 + ... + 696338.

It is an arithmetic number, because the mean of its divisors is an integer number (40622400).

Almost surely, 2^1938198816 is an apocalyptic number.

1938198816 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 1938198816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2924812800).

1938198816 is an abundant number, since it is smaller than the sum of its proper divisors (3911426784).

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

1938198816 is a wasteful number, since it uses less digits than its factorization.

1938198816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2951 (or 2940 counting only the distinct ones).

The product of its digits is 746496, while the sum is 54.

The square root of 1938198816 is about 44024.9794548504. The cubic root of 1938198816 is about 1246.8076012262.

The spelling of 1938198816 in words is "one billion, nine hundred thirty-eight million, one hundred ninety-eight thousand, eight hundred sixteen".