42161640889 has 27 divisors (see below), whose sum is σ = 45366344751. Its totient is φ = 39177536400.

The previous prime is 42161640881. The next prime is 42161640907. The reversal of 42161640889 is 98804616124.

It is a happy number.

The square root of 42161640889 is 205333.

It is a perfect power (a square), and thus also a powerful number.

42161640889 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 40508405289 + 1653235600 = 201267^2 + 40660^2 .

It is not a de Polignac number, because 42161640889 - 2³ = 42161640881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42161640881) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 394033974 + ... + 394034080.

Almost surely, 2^42161640889 is an apocalyptic number.

42161640889 is the 205333-rd square number.

42161640889 is the 102667-th centered octagonal number.

It is an amenable number.

42161640889 is a deficient number, since it is larger than the sum of its proper divisors (3204703862).

42161640889 is an equidigital number, since it uses as much as digits as its factorization.

42161640889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 49.

Multiplying 42161640889 by its sum of digits (49), we get a square (2065920403561 = 1437331²).

The spelling of 42161640889 in words is "forty-two billion, one hundred sixty-one million, six hundred forty thousand, eight hundred eighty-nine".