1261661633433 has 24 divisors (see below), whose sum is σ = 1842094871136. Its totient is φ = 832040640000.

The previous prime is 1261661633413. The next prime is 1261661633447. The reversal of 1261661633433 is 3343361661621.

It is a happy number.

1261661633433 is a `hidden beast` number, since 1 + 2 + 6 + 1 + 6 + 6 + 1 + 633 + 4 + 3 + 3 = 666.

It is not a de Polignac number, because 1261661633433 - 2⁶ = 1261661633369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1261661633413) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 282568 + ... + 1613433.

It is an arithmetic number, because the mean of its divisors is an integer number (76753952964).

Almost surely, 2^{1261661633433} is an apocalyptic number.

It is an amenable number.

1261661633433 is a deficient number, since it is larger than the sum of its proper divisors (580433237703).

1261661633433 is a wasteful number, since it uses less digits than its factorization.

1261661633433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1896805 (or 1896802 counting only the distinct ones).

The product of its digits is 839808, while the sum is 45.

The spelling of 1261661633433 in words is "one trillion, two hundred sixty-one billion, six hundred sixty-one million, six hundred thirty-three thousand, four hundred thirty-three".