1261013458536 has 256 divisors, whose sum is σ = 3825864806400. Its totient is φ = 382524519168.

The previous prime is 1261013458501. The next prime is 1261013458547. The reversal of 1261013458536 is 6358543101621.

1261013458536 is a `hidden beast` number, since 1 + 2 + 6 + 1 + 0 + 1 + 34 + 585 + 36 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 1261013458491 and 1261013458500.

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, 65644245 + ... + 65663451.

It is an arithmetic number, because the mean of its divisors is an integer number (14944784400).

Almost surely, 2^{1261013458536} 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 1261013458536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1912932403200).

1261013458536 is an abundant number, since it is smaller than the sum of its proper divisors (2564851347864).

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

1261013458536 is a wasteful number, since it uses less digits than its factorization.

1261013458536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19565 (or 19555 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 1261013458536 in words is "one trillion, two hundred sixty-one billion, thirteen million, four hundred fifty-eight thousand, five hundred thirty-six".