161838406 has 4 divisors (see below), whose sum is σ = 242757612. Its totient is φ = 80919202.

The previous prime is 161838403. The next prime is 161838431. The reversal of 161838406 is 604838161.

161838406 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 604838161 = 269 ⋅2248469.

It is a super-3 number, since 3×161838406³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161838403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40459600 + ... + 40459603.

It is an arithmetic number, because the mean of its divisors is an integer number (60689403).

Almost surely, 2^161838406 is an apocalyptic number.

161838406 is a deficient number, since it is larger than the sum of its proper divisors (80919206).

161838406 is an equidigital number, since it uses as much as digits as its factorization.

161838406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80919205.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 161838406 is about 12721.5724656978. The cubic root of 161838406 is about 544.9548608913.

The spelling of 161838406 in words is "one hundred sixty-one million, eight hundred thirty-eight thousand, four hundred six".