161663478 has 16 divisors (see below), whose sum is σ = 323606016. Its totient is φ = 53841320.

The previous prime is 161663477. The next prime is 161663479. The reversal of 161663478 is 874366161.

It is an interprime number because it is at equal distance from previous prime (161663477) and next prime (161663479).

It is a super-2 number, since 2×161663478² = 52270160238112968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161663473) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3678 + ... + 18353.

It is an arithmetic number, because the mean of its divisors is an integer number (20225376).

Almost surely, 2^161663478 is an apocalyptic number.

161663478 is an abundant number, since it is smaller than the sum of its proper divisors (161942538).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161663478 is a wasteful number, since it uses less digits than its factorization.

161663478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23259.

The product of its digits is 145152, while the sum is 42.

The square root of 161663478 is about 12714.6953561617. The cubic root of 161663478 is about 544.7584463876.

The spelling of 161663478 in words is "one hundred sixty-one million, six hundred sixty-three thousand, four hundred seventy-eight".