195661440 has 384 divisors, whose sum is σ = 761572800. Its totient is φ = 47443968.

The previous prime is 195661399. The next prime is 195661447. The reversal of 195661440 is 44166591.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 195661395 and 195661404.

It is not an unprimeable number, because it can be changed into a prime (195661447) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2920287 + ... + 2920353.

Almost surely, 2^195661440 is an apocalyptic number.

195661440 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 195661440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (380786400).

195661440 is an abundant number, since it is smaller than the sum of its proper divisors (565911360).

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

195661440 is a wasteful number, since it uses less digits than its factorization.

195661440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 195661440 is about 13987.9033453910. The cubic root of 195661440 is about 580.5439209869.

The spelling of 195661440 in words is "one hundred ninety-five million, six hundred sixty-one thousand, four hundred forty".