161766521 has 8 divisors (see below), whose sum is σ = 192914304. Its totient is φ = 132628320.

The previous prime is 161766511. The next prime is 161766533. The reversal of 161766521 is 125667161.

161766521 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 161766521 - 2⁶ = 161766457 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161766511) 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, 502220 + ... + 502541.

It is an arithmetic number, because the mean of its divisors is an integer number (24114288).

Almost surely, 2^161766521 is an apocalyptic number.

It is an amenable number.

161766521 is a deficient number, since it is larger than the sum of its proper divisors (31147783).

161766521 is a wasteful number, since it uses less digits than its factorization.

161766521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1004791.

The product of its digits is 15120, while the sum is 35.

The square root of 161766521 is about 12718.7468329234. The cubic root of 161766521 is about 544.8741633555.

It can be divided in two parts, 161 and 766521, that multiplied together give a square (123409881 = 11109²).

The spelling of 161766521 in words is "one hundred sixty-one million, seven hundred sixty-six thousand, five hundred twenty-one".