161121047 has 4 divisors (see below), whose sum is σ = 161720280. Its totient is φ = 160521816.

The previous prime is 161121041. The next prime is 161121067. The reversal of 161121047 is 740121161.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161121047 - 2⁶ = 161120983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161121041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 299213 + ... + 299750.

It is an arithmetic number, because the mean of its divisors is an integer number (40430070).

Almost surely, 2^161121047 is an apocalyptic number.

161121047 is a deficient number, since it is larger than the sum of its proper divisors (599233).

161121047 is an equidigital number, since it uses as much as digits as its factorization.

161121047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599232.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 161121047 is about 12693.3465642438. The cubic root of 161121047 is about 544.1484859500.

The spelling of 161121047 in words is "one hundred sixty-one million, one hundred twenty-one thousand, forty-seven".