161401535563 has 4 divisors (see below), whose sum is σ = 161402362120. Its totient is φ = 161400709008.

The previous prime is 161401535543. The next prime is 161401535567. The reversal of 161401535563 is 365535104161.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 365535104161 = 56123 ⋅6513107.

It is a cyclic number.

It is not a de Polignac number, because 161401535563 - 2⁹ = 161401535051 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161401535567) 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, 61231 + ... + 571447.

It is an arithmetic number, because the mean of its divisors is an integer number (40350590530).

Almost surely, 2^161401535563 is an apocalyptic number.

161401535563 is a deficient number, since it is larger than the sum of its proper divisors (826557).

161401535563 is an equidigital number, since it uses as much as digits as its factorization.

161401535563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 826556.

The product of its (nonzero) digits is 162000, while the sum is 40.

The spelling of 161401535563 in words is "one hundred sixty-one billion, four hundred one million, five hundred thirty-five thousand, five hundred sixty-three".