165421659 has 8 divisors (see below), whose sum is σ = 237528592. Its totient is φ = 101797920.

The previous prime is 165421621. The next prime is 165421687. The reversal of 165421659 is 956124561.

165421659 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 not a de Polignac number, because 165421659 - 2¹³ = 165413467 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 4241581 = 165421659 / (1 + 6 + 5 + 4 + 2 + 1 + 6 + 5 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165421159) 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, 2120752 + ... + 2120829.

It is an arithmetic number, because the mean of its divisors is an integer number (29691074).

Almost surely, 2^165421659 is an apocalyptic number.

165421659 is a deficient number, since it is larger than the sum of its proper divisors (72106933).

165421659 is a wasteful number, since it uses less digits than its factorization.

165421659 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4241597.

The product of its digits is 64800, while the sum is 39.

The square root of 165421659 is about 12861.6351604296. The cubic root of 165421659 is about 548.9474735828.

The spelling of 165421659 in words is "one hundred sixty-five million, four hundred twenty-one thousand, six hundred fifty-nine".