161664314403401 has 4 divisors (see below), whose sum is σ = 161664648176400. Its totient is φ = 161663980630404.

The previous prime is 161664314403391. The next prime is 161664314403407. The reversal of 161664314403401 is 104304413466161.

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.

It is a cyclic number.

It is not a de Polignac number, because 161664314403401 - 2²² = 161664310209097 is a prime.

It is a super-2 number, since 2×161664314403401² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161664314403407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166158911 + ... + 167129028.

It is an arithmetic number, because the mean of its divisors is an integer number (40416162044100).

Almost surely, 2^{161664314403401} is an apocalyptic number.

It is an amenable number.

161664314403401 is a deficient number, since it is larger than the sum of its proper divisors (333772999).

161664314403401 is an equidigital number, since it uses as much as digits as its factorization.

161664314403401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333772998.

The product of its (nonzero) digits is 497664, while the sum is 44.

Adding to 161664314403401 its reverse (104304413466161), we get a palindrome (265968727869562).

The spelling of 161664314403401 in words is "one hundred sixty-one trillion, six hundred sixty-four billion, three hundred fourteen million, four hundred three thousand, four hundred one".