1761221025745 has 4 divisors (see below), whose sum is σ = 2113465230900. Its totient is φ = 1408976820592.

The previous prime is 1761221025643. The next prime is 1761221025757. The reversal of 1761221025745 is 5475201221671.

1761221025745 = 938408² + 938409².

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 880609574464 + 880611451281 = 938408^2 + 938409^2 .

It is a cyclic number.

It is not a de Polignac number, because 1761221025745 - 2²⁹ = 1760684154833 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176122102570 + ... + 176122102579.

It is an arithmetic number, because the mean of its divisors is an integer number (528366307725).

Almost surely, 2^{1761221025745} is an apocalyptic number.

1761221025745 is the 938409-th centered square number.

It is an amenable number.

1761221025745 is a deficient number, since it is larger than the sum of its proper divisors (352244205155).

1761221025745 is an equidigital number, since it uses as much as digits as its factorization.

1761221025745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352244205154.

The product of its (nonzero) digits is 235200, while the sum is 43.

The spelling of 1761221025745 in words is "one trillion, seven hundred sixty-one billion, two hundred twenty-one million, twenty-five thousand, seven hundred forty-five".