199961903240 has 128 divisors (see below), whose sum is σ = 497000085120. Its totient is φ = 71800627200.

The previous prime is 199961903171. The next prime is 199961903257. The reversal of 199961903240 is 42309169991.

It is a happy number.

It is a Cunningham number, because it is equal to 447171²-1.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19670399 + ... + 19680561.

It is an arithmetic number, because the mean of its divisors is an integer number (3882813165).

Almost surely, 2^199961903240 is an apocalyptic number.

199961903240 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 199961903240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (248500042560).

199961903240 is an abundant number, since it is smaller than the sum of its proper divisors (297038181880).

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

199961903240 is a wasteful number, since it uses less digits than its factorization.

199961903240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10743 (or 10739 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 53.

The spelling of 199961903240 in words is "one hundred ninety-nine billion, nine hundred sixty-one million, nine hundred three thousand, two hundred forty".