645442266 has 32 divisors (see below), whose sum is σ = 1481817600. Its totient is φ = 183596976.

The previous prime is 645442253. The next prime is 645442271. The reversal of 645442266 is 662244546.

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, 24316 + ... + 43383.

It is an arithmetic number, because the mean of its divisors is an integer number (46306800).

Almost surely, 2^645442266 is an apocalyptic number.

645442266 is an abundant number, since it is smaller than the sum of its proper divisors (836375334).

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

645442266 is a wasteful number, since it uses less digits than its factorization.

645442266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67938.

The product of its digits is 276480, while the sum is 39.

The square root of 645442266 is about 25405.5558097043. Note that the first 3 decimals coincide. The cubic root of 645442266 is about 864.2096943659.

The spelling of 645442266 in words is "six hundred forty-five million, four hundred forty-two thousand, two hundred sixty-six".