165661455 has 16 divisors (see below), whose sum is σ = 268691040. Its totient is φ = 87141888.

The previous prime is 165661409. The next prime is 165661471. The reversal of 165661455 is 554166561.

It is not a de Polignac number, because 165661455 - 2¹⁶ = 165595919 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74550 + ... + 76739.

It is an arithmetic number, because the mean of its divisors is an integer number (16793190).

Almost surely, 2^165661455 is an apocalyptic number.

165661455 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

165661455 is a deficient number, since it is larger than the sum of its proper divisors (103029585).

165661455 is a wasteful number, since it uses less digits than its factorization.

165661455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151370.

The product of its digits is 108000, while the sum is 39.

The square root of 165661455 is about 12870.9539273513. The cubic root of 165661455 is about 549.2125977790.

The spelling of 165661455 in words is "one hundred sixty-five million, six hundred sixty-one thousand, four hundred fifty-five".