161728432490 has 8 divisors (see below), whose sum is σ = 291111178500. Its totient is φ = 64691372992.

The previous prime is 161728432487. The next prime is 161728432493. The reversal of 161728432490 is 94234827161.

It is an interprime number because it is at equal distance from previous prime (161728432487) and next prime (161728432493).

It can be written as a sum of positive squares in 2 ways, for example, as 146307015001 + 15421417489 = 382501^2 + 124183^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161728432493) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 8086421615 + ... + 8086421634.

Almost surely, 2^161728432490 is an apocalyptic number.

161728432490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161728432490 is a deficient number, since it is larger than the sum of its proper divisors (129382746010).

161728432490 is a wasteful number, since it uses less digits than its factorization.

161728432490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16172843256.

The product of its (nonzero) digits is 580608, while the sum is 47.

The spelling of 161728432490 in words is "one hundred sixty-one billion, seven hundred twenty-eight million, four hundred thirty-two thousand, four hundred ninety".