169428421 has 4 divisors (see below), whose sum is σ = 170027392. Its totient is φ = 168829452.

The previous prime is 169428403. The next prime is 169428433. The reversal of 169428421 is 124824961.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 124824961 = 29 ⋅4304309.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-169428421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (169428221) 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, 299061 + ... + 299626.

It is an arithmetic number, because the mean of its divisors is an integer number (42506848).

Almost surely, 2^169428421 is an apocalyptic number.

It is an amenable number.

169428421 is a deficient number, since it is larger than the sum of its proper divisors (598971).

169428421 is an equidigital number, since it uses as much as digits as its factorization.

169428421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 598970.

The product of its digits is 27648, while the sum is 37.

The square root of 169428421 is about 13016.4673010767. The cubic root of 169428421 is about 553.3442751582.

The spelling of 169428421 in words is "one hundred sixty-nine million, four hundred twenty-eight thousand, four hundred twenty-one".