161890104043 has 4 divisors (see below), whose sum is σ = 165838643208. Its totient is φ = 157941564880.

The previous prime is 161890104007. The next prime is 161890104119. The reversal of 161890104043 is 340401098161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161890104043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161890103993 and 161890104011.

It is not an unprimeable number, because it can be changed into a prime (161890104643) 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, 1974269521 + ... + 1974269602.

It is an arithmetic number, because the mean of its divisors is an integer number (41459660802).

Almost surely, 2^161890104043 is an apocalyptic number.

161890104043 is a deficient number, since it is larger than the sum of its proper divisors (3948539165).

161890104043 is an equidigital number, since it uses as much as digits as its factorization.

161890104043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3948539164.

The product of its (nonzero) digits is 20736, while the sum is 37.

The spelling of 161890104043 in words is "one hundred sixty-one billion, eight hundred ninety million, one hundred four thousand, forty-three".