161521301671042 has 4 divisors (see below), whose sum is σ = 242281952506566. Its totient is φ = 80760650835520.

The previous prime is 161521301671019. The next prime is 161521301671057. The reversal of 161521301671042 is 240176103125161.

161521301671042 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

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., 120065074971241 + 41456226699801 = 10957421^2 + 6438651^2 .

It is a junction number, because it is equal to n+sod(n) for n = 161521301670986 and 161521301671004.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40380325417759 + ... + 40380325417762.

Almost surely, 2^{161521301671042} is an apocalyptic number.

161521301671042 is a deficient number, since it is larger than the sum of its proper divisors (80760650835524).

161521301671042 is an equidigital number, since it uses as much as digits as its factorization.

161521301671042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80760650835523.

The product of its (nonzero) digits is 60480, while the sum is 40.

The spelling of 161521301671042 in words is "one hundred sixty-one trillion, five hundred twenty-one billion, three hundred one million, six hundred seventy-one thousand, forty-two".