1261051311340 has 24 divisors (see below), whose sum is σ = 2650203444672. Its totient is φ = 504040392960.

The previous prime is 1261051311323. The next prime is 1261051311343. The reversal of 1261051311340 is 431131501621.

It is a super-2 number, since 2×1261051311340² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1261051311299 and 1261051311308.

It is not an unprimeable number, because it can be changed into a prime (1261051311343) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23731021 + ... + 23784100.

It is an arithmetic number, because the mean of its divisors is an integer number (110425143528).

Almost surely, 2^{1261051311340} is an apocalyptic number.

1261051311340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1261051311340 is an abundant number, since it is smaller than the sum of its proper divisors (1389152133332).

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

1261051311340 is a wasteful number, since it uses less digits than its factorization.

1261051311340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47516457 (or 47516455 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

Adding to 1261051311340 its reverse (431131501621), we get a palindrome (1692182812961).

The spelling of 1261051311340 in words is "one trillion, two hundred sixty-one billion, fifty-one million, three hundred eleven thousand, three hundred forty".