161616405 has 8 divisors (see below), whose sum is σ = 258586272. Its totient is φ = 86195408.

The previous prime is 161616353. The next prime is 161616419. The reversal of 161616405 is 504616161.

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

It is a cyclic number.

It is not a de Polignac number, because 161616405 - 2⁸ = 161616149 is a prime.

It is a super-2 number, since 2×161616405² = 52239724730248050, which contains 22 as substring.

It is a congruent number.

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, 5387199 + ... + 5387228.

It is an arithmetic number, because the mean of its divisors is an integer number (32323284).

Almost surely, 2^161616405 is an apocalyptic number.

161616405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161616405 is a deficient number, since it is larger than the sum of its proper divisors (96969867).

161616405 is a wasteful number, since it uses less digits than its factorization.

161616405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10774435.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 161616405 is about 12712.8440956381. The cubic root of 161616405 is about 544.7055671927.

The spelling of 161616405 in words is "one hundred sixty-one million, six hundred sixteen thousand, four hundred five".