195138312840 has 128 divisors (see below), whose sum is σ = 652274208000. Its totient is φ = 51891830784.

The previous prime is 195138312821. The next prime is 195138312847. The reversal of 195138312840 is 48213831591.

195138312840 is a `hidden beast` number, since 1 + 9 + 513 + 8 + 3 + 128 + 4 + 0 = 666.

195138312840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×195138312840² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (195138312847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 136072 + ... + 639368.

It is an arithmetic number, because the mean of its divisors is an integer number (5095892250).

Almost surely, 2^195138312840 is an apocalyptic number.

195138312840 is a gapful number since it is divisible by the number (10) 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 195138312840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326137104000).

195138312840 is an abundant number, since it is smaller than the sum of its proper divisors (457135895160).

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

195138312840 is a wasteful number, since it uses less digits than its factorization.

195138312840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503676 (or 503666 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 195138312840 in words is "one hundred ninety-five billion, one hundred thirty-eight million, three hundred twelve thousand, eight hundred forty".