1261115807952 has 320 divisors, whose sum is σ = 4604445296640. Its totient is φ = 286451251200.

The previous prime is 1261115807947. The next prime is 1261115807953. The reversal of 1261115807952 is 2597085111621.

It is a hoax number, since the sum of its digits (48) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261115807953) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 222202 + ... + 1603622.

It is an arithmetic number, because the mean of its divisors is an integer number (14388891552).

Almost surely, 2^{1261115807952} is an apocalyptic number.

1261115807952 is a gapful number since it is divisible by the number (12) 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 1261115807952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2302222648320).

1261115807952 is an abundant number, since it is smaller than the sum of its proper divisors (3343329488688).

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

1261115807952 is a wasteful number, since it uses less digits than its factorization.

1261115807952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381482 (or 1381476 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 48.

The spelling of 1261115807952 in words is "one trillion, two hundred sixty-one billion, one hundred fifteen million, eight hundred seven thousand, nine hundred fifty-two".