1261323095616 has 448 divisors, whose sum is σ = 3908809820160. Its totient is φ = 398078208000.

The previous prime is 1261323095551. The next prime is 1261323095671. The reversal of 1261323095616 is 6165903231621.

1261323095616 is a `hidden beast` number, since 1 + 2 + 6 + 1 + 3 + 23 + 0 + 9 + 5 + 616 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2264493610 + ... + 2264494166.

It is an arithmetic number, because the mean of its divisors is an integer number (8725021920).

Almost surely, 2^{1261323095616} is an apocalyptic number.

1261323095616 is a gapful number since it is divisible by the number (16) 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 1261323095616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1954404910080).

1261323095616 is an abundant number, since it is smaller than the sum of its proper divisors (2647486724544).

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

1261323095616 is a wasteful number, since it uses less digits than its factorization.

1261323095616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1079 (or 1063 counting only the distinct ones).

The product of its (nonzero) digits is 349920, while the sum is 45.

The spelling of 1261323095616 in words is "one trillion, two hundred sixty-one billion, three hundred twenty-three million, ninety-five thousand, six hundred sixteen".