161887400023 has 4 divisors (see below), whose sum is σ = 161896943728. Its totient is φ = 161877856320.

The previous prime is 161887399967. The next prime is 161887400083. The reversal of 161887400023 is 320004788161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 320004788161 = 751 ⋅426104911.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161887400023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161887400083) 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, 4746363 + ... + 4780348.

It is an arithmetic number, because the mean of its divisors is an integer number (40474235932).

Almost surely, 2^161887400023 is an apocalyptic number.

161887400023 is a deficient number, since it is larger than the sum of its proper divisors (9543705).

161887400023 is an equidigital number, since it uses as much as digits as its factorization.

161887400023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9543704.

The product of its (nonzero) digits is 64512, while the sum is 40.

The spelling of 161887400023 in words is "one hundred sixty-one billion, eight hundred eighty-seven million, four hundred thousand, twenty-three".