161873401 has 4 divisors (see below), whose sum is σ = 162070912. Its totient is φ = 161675892.

The previous prime is 161873399. The next prime is 161873419. The reversal of 161873401 is 104378161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 104378161 = 67 ⋅1557883.

It is a cyclic number.

It is not a de Polignac number, because 161873401 - 2¹ = 161873399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161873431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97521 + ... + 99166.

It is an arithmetic number, because the mean of its divisors is an integer number (40517728).

Almost surely, 2^161873401 is an apocalyptic number.

It is an amenable number.

161873401 is a deficient number, since it is larger than the sum of its proper divisors (197511).

161873401 is an equidigital number, since it uses as much as digits as its factorization.

161873401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197510.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 161873401 is about 12722.9478109438. The cubic root of 161873401 is about 544.9941373552.

The spelling of 161873401 in words is "one hundred sixty-one million, eight hundred seventy-three thousand, four hundred one".