161503167453581 has 8 divisors (see below), whose sum is σ = 161728477372800. Its totient is φ = 161277859446880.

The previous prime is 161503167453553. The next prime is 161503167453601. The reversal of 161503167453581 is 185354761305161.

161503167453581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161503167453581 - 2¹⁸ = 161503167191437 is a prime.

It is a super-2 number, since 2×161503167453581² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161503167453521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 299855201 + ... + 300393321.

It is an arithmetic number, because the mean of its divisors is an integer number (20216059671600).

Almost surely, 2^{161503167453581} is an apocalyptic number.

It is an amenable number.

161503167453581 is a deficient number, since it is larger than the sum of its proper divisors (225309919219).

161503167453581 is an equidigital number, since it uses as much as digits as its factorization.

161503167453581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956259.

The product of its (nonzero) digits is 9072000, while the sum is 56.

The spelling of 161503167453581 in words is "one hundred sixty-one trillion, five hundred three billion, one hundred sixty-seven million, four hundred fifty-three thousand, five hundred eighty-one".