645666546 has 32 divisors (see below), whose sum is σ = 1476616320. Its totient is φ = 184375296.

The previous prime is 645666503. The next prime is 645666563.

It is a happy number.

645666546 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 645666495 and 645666504.

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, 110080 + ... + 115796.

It is an arithmetic number, because the mean of its divisors is an integer number (46144260).

Almost surely, 2^645666546 is an apocalyptic number.

645666546 is an abundant number, since it is smaller than the sum of its proper divisors (830949774).

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

645666546 is a wasteful number, since it uses less digits than its factorization.

645666546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8418.

The product of its digits is 3110400, while the sum is 48.

The square root of 645666546 is about 25409.9694214692. The cubic root of 645666546 is about 864.3097820704.

The spelling of 645666546 in words is "six hundred forty-five million, six hundred sixty-six thousand, five hundred forty-six".