161869231 has 2 divisors, whose sum is σ = 161869232. Its totient is φ = 161869230.

The previous prime is 161869219. The next prime is 161869241. The reversal of 161869231 is 132968161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161869231 - 2⁹ = 161868719 is a prime.

It is a super-2 number, since 2×161869231² = 52403295889062722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161869241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80934615 + 80934616.

It is an arithmetic number, because the mean of its divisors is an integer number (80934616).

Almost surely, 2^161869231 is an apocalyptic number.

161869231 is a deficient number, since it is larger than the sum of its proper divisors (1).

161869231 is an equidigital number, since it uses as much as digits as its factorization.

161869231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 37.

The square root of 161869231 is about 12722.7839327719. The cubic root of 161869231 is about 544.9894574736.

The spelling of 161869231 in words is "one hundred sixty-one million, eight hundred sixty-nine thousand, two hundred thirty-one".