2171157765 has 16 divisors (see below), whose sum is σ = 3970117248. Its totient is φ = 992529216.

The previous prime is 2171157739. The next prime is 2171157787. The reversal of 2171157765 is 5677511712.

It is not a de Polignac number, because 2171157765 - 2⁶ = 2171157701 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10338742 + ... + 10338951.

It is an arithmetic number, because the mean of its divisors is an integer number (248132328).

Almost surely, 2^2171157765 is an apocalyptic number.

It is an amenable number.

2171157765 is a deficient number, since it is larger than the sum of its proper divisors (1798959483).

2171157765 is a wasteful number, since it uses less digits than its factorization.

2171157765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20677708.

The product of its digits is 102900, while the sum is 42.

The square root of 2171157765 is about 46595.6839739476. The cubic root of 2171157765 is about 1294.8827957512.

The spelling of 2171157765 in words is "two billion, one hundred seventy-one million, one hundred fifty-seven thousand, seven hundred sixty-five".