161278547 has 4 divisors (see below), whose sum is σ = 161663880. Its totient is φ = 160893216.

The previous prime is 161278531. The next prime is 161278549. The reversal of 161278547 is 745872161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 745872161 = 17 ⋅43874833.

It is a cyclic number.

It is not a de Polignac number, because 161278547 - 2⁴ = 161278531 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161278549) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192038 + ... + 192875.

It is an arithmetic number, because the mean of its divisors is an integer number (40415970).

Almost surely, 2^161278547 is an apocalyptic number.

161278547 is a deficient number, since it is larger than the sum of its proper divisors (385333).

161278547 is an equidigital number, since it uses as much as digits as its factorization.

161278547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 385332.

The product of its digits is 94080, while the sum is 41.

The square root of 161278547 is about 12699.5490864833. The cubic root of 161278547 is about 544.3257346242.

The spelling of 161278547 in words is "one hundred sixty-one million, two hundred seventy-eight thousand, five hundred forty-seven".