161538554087 has 4 divisors (see below), whose sum is σ = 161941393776. Its totient is φ = 161135714400.

The previous prime is 161538554083. The next prime is 161538554141. The reversal of 161538554087 is 780455835161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 780455835161 = 131 ⋅5957678131.

It is a cyclic number.

It is not a de Polignac number, because 161538554087 - 2² = 161538554083 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 (161538554083) 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, 201419243 + ... + 201420044.

It is an arithmetic number, because the mean of its divisors is an integer number (40485348444).

Almost surely, 2^161538554087 is an apocalyptic number.

161538554087 is a deficient number, since it is larger than the sum of its proper divisors (402839689).

161538554087 is an equidigital number, since it uses as much as digits as its factorization.

161538554087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402839688.

The product of its (nonzero) digits is 4032000, while the sum is 53.

The spelling of 161538554087 in words is "one hundred sixty-one billion, five hundred thirty-eight million, five hundred fifty-four thousand, eighty-seven".