161156542 has 4 divisors (see below), whose sum is σ = 241734816. Its totient is φ = 80578270.

The previous prime is 161156539. The next prime is 161156543. The reversal of 161156542 is 245651161.

161156542 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161156543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40289134 + ... + 40289137.

It is an arithmetic number, because the mean of its divisors is an integer number (60433704).

Almost surely, 2^161156542 is an apocalyptic number.

161156542 is a deficient number, since it is larger than the sum of its proper divisors (80578274).

161156542 is an equidigital number, since it uses as much as digits as its factorization.

161156542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80578273.

The product of its digits is 7200, while the sum is 31.

The square root of 161156542 is about 12694.7446606854. The cubic root of 161156542 is about 544.1884416907.

The spelling of 161156542 in words is "one hundred sixty-one million, one hundred fifty-six thousand, five hundred forty-two".