645413266 has 4 divisors (see below), whose sum is σ = 968119902. Its totient is φ = 322706632.

The previous prime is 645413243. The next prime is 645413287. The reversal of 645413266 is 662314546.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 429940225 + 215473041 = 20735^2 + 14679^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161353315 + ... + 161353318.

Almost surely, 2^645413266 is an apocalyptic number.

645413266 is a deficient number, since it is larger than the sum of its proper divisors (322706636).

645413266 is a wasteful number, since it uses less digits than its factorization.

645413266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322706635.

The product of its digits is 103680, while the sum is 37.

The square root of 645413266 is about 25404.9850619913. The cubic root of 645413266 is about 864.1967510670.

The spelling of 645413266 in words is "six hundred forty-five million, four hundred thirteen thousand, two hundred sixty-six".