161554642 has 4 divisors (see below), whose sum is σ = 242331966. Its totient is φ = 80777320.

The previous prime is 161554639. The next prime is 161554643. The reversal of 161554642 is 246455161.

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

It can be written as a sum of positive squares in only one way, i.e., 125686521 + 35868121 = 11211^2 + 5989^2 .

It is a junction number, because it is equal to n+sod(n) for n = 161554598 and 161554607.

It is not an unprimeable number, because it can be changed into a prime (161554643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40388659 + ... + 40388662.

Almost surely, 2^161554642 is an apocalyptic number.

161554642 is a deficient number, since it is larger than the sum of its proper divisors (80777324).

161554642 is an equidigital number, since it uses as much as digits as its factorization.

161554642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80777323.

The product of its digits is 28800, while the sum is 34.

The square root of 161554642 is about 12710.4147060590. The cubic root of 161554642 is about 544.6361704908.

The spelling of 161554642 in words is "one hundred sixty-one million, five hundred fifty-four thousand, six hundred forty-two".