1261450514661 has 32 divisors (see below), whose sum is σ = 1788056000640. Its totient is φ = 789537159936.

The previous prime is 1261450514651. The next prime is 1261450514663. The reversal of 1261450514661 is 1664150541621.

It is not a de Polignac number, because 1261450514661 - 2¹¹ = 1261450512613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261450514663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5149810 + ... + 5389196.

It is an arithmetic number, because the mean of its divisors is an integer number (55876750020).

Almost surely, 2^{1261450514661} is an apocalyptic number.

It is an amenable number.

1261450514661 is a deficient number, since it is larger than the sum of its proper divisors (526605485979).

1261450514661 is a wasteful number, since it uses less digits than its factorization.

1261450514661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241093.

The product of its (nonzero) digits is 172800, while the sum is 42.

The spelling of 1261450514661 in words is "one trillion, two hundred sixty-one billion, four hundred fifty million, five hundred fourteen thousand, six hundred sixty-one".