645499404994546 has 16 divisors (see below), whose sum is σ = 1010631740503104. Its totient is φ = 308630070541584.

The previous prime is 645499404994489. The next prime is 645499404994567.

645499404994546 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×645499404994546² (a number of 30 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 645499404994546.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1977930405 + ... + 1978256728.

It is an arithmetic number, because the mean of its divisors is an integer number (63164483781444).

Almost surely, 2^{645499404994546} is an apocalyptic number.

645499404994546 is a deficient number, since it is larger than the sum of its proper divisors (365132335508558).

645499404994546 is a wasteful number, since it uses less digits than its factorization.

645499404994546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3956190705.

The product of its (nonzero) digits is 24186470400, while the sum is 82.

The spelling of 645499404994546 in words is "six hundred forty-five trillion, four hundred ninety-nine billion, four hundred four million, nine hundred ninety-four thousand, five hundred forty-six".