161643455 has 8 divisors (see below), whose sum is σ = 200229504. Its totient is φ = 125143200.

The previous prime is 161643439. The next prime is 161643457. The reversal of 161643455 is 554346161.

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

It is not a de Polignac number, because 161643455 - 2⁴ = 161643439 is a prime.

It is a super-2 number, since 2×161643455² = 52257213088674050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161643457) 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, 521276 + ... + 521585.

It is an arithmetic number, because the mean of its divisors is an integer number (25028688).

Almost surely, 2^161643455 is an apocalyptic number.

161643455 is a deficient number, since it is larger than the sum of its proper divisors (38586049).

161643455 is a wasteful number, since it uses less digits than its factorization.

161643455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1042897.

The product of its digits is 43200, while the sum is 35.

The square root of 161643455 is about 12713.9079358001. The cubic root of 161643455 is about 544.7359549157.

The spelling of 161643455 in words is "one hundred sixty-one million, six hundred forty-three thousand, four hundred fifty-five".