161919469 has 2 divisors, whose sum is σ = 161919470. Its totient is φ = 161919468.

The previous prime is 161919421. The next prime is 161919487. The reversal of 161919469 is 964919161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139004100 + 22915369 = 11790^2 + 4787^2 .

It is a cyclic number.

It is not a de Polignac number, because 161919469 - 2¹¹ = 161917421 is a prime.

It is a super-2 number, since 2×161919469² = 52435828882483922, which contains 22 as substring.

It is equal to p_9075979 and since 161919469 and 9075979 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161919409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80959734 + 80959735.

It is an arithmetic number, because the mean of its divisors is an integer number (80959735).

Almost surely, 2^161919469 is an apocalyptic number.

It is an amenable number.

161919469 is a deficient number, since it is larger than the sum of its proper divisors (1).

161919469 is an equidigital number, since it uses as much as digits as its factorization.

161919469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 104976, while the sum is 46.

The square root of 161919469 is about 12724.7581116499. The cubic root of 161919469 is about 545.0458329157.

The spelling of 161919469 in words is "one hundred sixty-one million, nine hundred nineteen thousand, four hundred sixty-nine".