161210133445 has 4 divisors (see below), whose sum is σ = 193452160140. Its totient is φ = 128968106752.

The previous prime is 161210133419. The next prime is 161210133467. The reversal of 161210133445 is 544331012161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 544331012161 = 53773 ⋅10122757.

It can be written as a sum of positive squares in 2 ways, for example, as 113176397889 + 48033735556 = 336417^2 + 219166^2 .

It is a cyclic number.

It is not a de Polignac number, because 161210133445 - 2⁹ = 161210132933 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16121013340 + ... + 16121013349.

It is an arithmetic number, because the mean of its divisors is an integer number (48363040035).

Almost surely, 2^161210133445 is an apocalyptic number.

It is an amenable number.

161210133445 is a deficient number, since it is larger than the sum of its proper divisors (32242026695).

161210133445 is an equidigital number, since it uses as much as digits as its factorization.

161210133445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32242026694.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 161210133445 in words is "one hundred sixty-one billion, two hundred ten million, one hundred thirty-three thousand, four hundred forty-five".