645767546 has 4 divisors (see below), whose sum is σ = 968651322. Its totient is φ = 322883772.

The previous prime is 645767543. The next prime is 645767561.

645767546 is nontrivially palindromic in base 10.

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., 456292321 + 189475225 = 21361^2 + 13765^2 .

It is a junction number, because it is equal to n+sod(n) for n = 645767494 and 645767503.

It is not an unprimeable number, because it can be changed into a prime (645767543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161441885 + ... + 161441888.

Almost surely, 2^645767546 is an apocalyptic number.

645767546 is a deficient number, since it is larger than the sum of its proper divisors (322883776).

645767546 is a wasteful number, since it uses less digits than its factorization.

645767546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322883775.

The product of its digits is 4233600, while the sum is 50.

The square root of 645767546 is about 25411.9567526785. The cubic root of 645767546 is about 864.3548469918.

The spelling of 645767546 in words is "six hundred forty-five million, seven hundred sixty-seven thousand, five hundred forty-six".