9781000640496 has 120 divisors (see below), whose sum is σ = 27618706258416. Its totient is φ = 3231100938240.

The previous prime is 9781000640491. The next prime is 9781000640497. The reversal of 9781000640496 is 6940460001879.

9781000640496 is a `hidden beast` number, since 9 + 7 + 8 + 100 + 0 + 6 + 40 + 496 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9781000640491) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 160785766 + ... + 160846586.

Almost surely, 2^{9781000640496} 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 9781000640496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13809353129208).

9781000640496 is an abundant number, since it is smaller than the sum of its proper divisors (17837705617920).

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

9781000640496 is a wasteful number, since it uses less digits than its factorization.

9781000640496 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70831 (or 70822 counting only the distinct ones).

The product of its (nonzero) digits is 2612736, while the sum is 54.

The spelling of 9781000640496 in words is "nine trillion, seven hundred eighty-one billion, six hundred forty thousand, four hundred ninety-six".