1261316131621 has 64 divisors (see below), whose sum is σ = 1668444825600. Its totient is φ = 925693920000.

The previous prime is 1261316131609. The next prime is 1261316131661.

1261316131621 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 1261316131621 - 2³³ = 1252726197029 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261316131661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 25580131 + ... + 25629391.

It is an arithmetic number, because the mean of its divisors is an integer number (26069450400).

Almost surely, 2^{1261316131621} is an apocalyptic number.

It is an amenable number.

1261316131621 is a deficient number, since it is larger than the sum of its proper divisors (407128693979).

1261316131621 is a wasteful number, since it uses less digits than its factorization.

1261316131621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49610.

The product of its digits is 7776, while the sum is 34.

The spelling of 1261316131621 in words is "one trillion, two hundred sixty-one billion, three hundred sixteen million, one hundred thirty-one thousand, six hundred twenty-one".