161451638 has 16 divisors (see below), whose sum is σ = 244245456. Its totient is φ = 80039520.

The previous prime is 161451617. The next prime is 161451643. The reversal of 161451638 is 836154161.

It is a junction number, because it is equal to n+sod(n) for n = 161451598 and 161451607.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 236045 + ... + 236727.

It is an arithmetic number, because the mean of its divisors is an integer number (15265341).

Almost surely, 2^161451638 is an apocalyptic number.

161451638 is a deficient number, since it is larger than the sum of its proper divisors (82793818).

161451638 is a wasteful number, since it uses less digits than its factorization.

161451638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1519.

The product of its digits is 17280, while the sum is 35.

The square root of 161451638 is about 12706.3621072280. The cubic root of 161451638 is about 544.5203961820.

The spelling of 161451638 in words is "one hundred sixty-one million, four hundred fifty-one thousand, six hundred thirty-eight".