42779161 has 2 divisors, whose sum is σ = 42779162. Its totient is φ = 42779160.

The previous prime is 42779137. The next prime is 42779167. The reversal of 42779161 is 16197724.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39000025 + 3779136 = 6245^2 + 1944^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42779161 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 42779161.

It is not a weakly prime, because it can be changed into another prime (42779167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21389580 + 21389581.

It is an arithmetic number, because the mean of its divisors is an integer number (21389581).

Almost surely, 2^42779161 is an apocalyptic number.

It is an amenable number.

42779161 is a deficient number, since it is larger than the sum of its proper divisors (1).

42779161 is an equidigital number, since it uses as much as digits as its factorization.

42779161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 37.

The square root of 42779161 is about 6540.5780325595. The cubic root of 42779161 is about 349.7390190508.

The spelling of 42779161 in words is "forty-two million, seven hundred seventy-nine thousand, one hundred sixty-one".