669542428 has 24 divisors (see below), whose sum is σ = 1202448240. Its totient is φ = 326077440.

The previous prime is 669542413. The next prime is 669542429. The reversal of 669542428 is 824245966.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669542429) 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, 18108 + ... + 40828.

It is an arithmetic number, because the mean of its divisors is an integer number (50102010).

Almost surely, 2^669542428 is an apocalyptic number.

It is an amenable number.

669542428 is a deficient number, since it is larger than the sum of its proper divisors (532905812).

669542428 is a wasteful number, since it uses less digits than its factorization.

669542428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22917 (or 22915 counting only the distinct ones).

The product of its digits is 829440, while the sum is 46.

The square root of 669542428 is about 25875.5179271836. The cubic root of 669542428 is about 874.8347673849.

The spelling of 669542428 in words is "six hundred sixty-nine million, five hundred forty-two thousand, four hundred twenty-eight".