961991962500 has 288 divisors, whose sum is σ = 3099874095360. Its totient is φ = 230940160000.

The previous prime is 961991962489. The next prime is 961991962507. The reversal of 961991962500 is 5269199169.

It is not an unprimeable number, because it can be changed into a prime (961991962507) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 14629696 + ... + 14695304.

It is an arithmetic number, because the mean of its divisors is an integer number (10763451720).

Almost surely, 2^961991962500 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 961991962500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1549937047680).

961991962500 is an abundant number, since it is smaller than the sum of its proper divisors (2137882132860).

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

961991962500 is a wasteful number, since it uses less digits than its factorization.

961991962500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65681 (or 65659 counting only the distinct ones).

The product of its (nonzero) digits is 2361960, while the sum is 57.

The spelling of 961991962500 in words is "nine hundred sixty-one billion, nine hundred ninety-one million, nine hundred sixty-two thousand, five hundred".