66620428 has 24 divisors (see below), whose sum is σ = 133441952. Its totient is φ = 28508544.

The previous prime is 66620423. The next prime is 66620429. The reversal of 66620428 is 82402666.

It is a junction number, because it is equal to n+sod(n) for n = 66620393 and 66620402.

It is not an unprimeable number, because it can be changed into a prime (66620423) 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, 23200 + ... + 25912.

Almost surely, 2^66620428 is an apocalyptic number.

It is an amenable number.

66620428 is an abundant number, since it is smaller than the sum of its proper divisors (66821524).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66620428 is a wasteful number, since it uses less digits than its factorization.

66620428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3601 (or 3599 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 66620428 is about 8162.1337896410. The cubic root of 66620428 is about 405.3863670533.

The spelling of 66620428 in words is "sixty-six million, six hundred twenty thousand, four hundred twenty-eight".