161221174575442 has 16 divisors (see below), whose sum is σ = 243311466384000. Its totient is φ = 80118234012960.

The previous prime is 161221174575379. The next prime is 161221174575467. The reversal of 161221174575442 is 244575471122161.

It is a self number, because there is not a number n which added to its sum of digits gives 161221174575442.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220025059 + ... + 220756582.

It is an arithmetic number, because the mean of its divisors is an integer number (15206966649000).

Almost surely, 2^{161221174575442} is an apocalyptic number.

161221174575442 is a deficient number, since it is larger than the sum of its proper divisors (82090291808558).

161221174575442 is a wasteful number, since it uses less digits than its factorization.

161221174575442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440782761.

The product of its digits is 3763200, while the sum is 52.

The spelling of 161221174575442 in words is "one hundred sixty-one trillion, two hundred twenty-one billion, one hundred seventy-four million, five hundred seventy-five thousand, four hundred forty-two".