766161561 has 16 divisors (see below), whose sum is σ = 1116630720. Its totient is φ = 463417920.

The previous prime is 766161511. The next prime is 766161589. The reversal of 766161561 is 165161667.

It is not a de Polignac number, because 766161561 - 2¹⁵ = 766128793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (766161511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6010 + ... + 39603.

It is an arithmetic number, because the mean of its divisors is an integer number (69789420).

Almost surely, 2^766161561 is an apocalyptic number.

It is an amenable number.

766161561 is a deficient number, since it is larger than the sum of its proper divisors (350469159).

766161561 is a wasteful number, since it uses less digits than its factorization.

766161561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46136.

The product of its digits is 45360, while the sum is 39.

The square root of 766161561 is about 27679.6235704173. The cubic root of 766161561 is about 915.0400854367.

The spelling of 766161561 in words is "seven hundred sixty-six million, one hundred sixty-one thousand, five hundred sixty-one".