645969546 has 16 divisors (see below), whose sum is σ = 1435488000. Its totient is φ = 215323164.

The previous prime is 645969517. The next prime is 645969617.

645969546 is a `hidden beast` number, since 6 + 4 + 5 + 96 + 9 + 546 = 666.

645969546 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×645969546² = 834553308718892232, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 11962399 = 645969546 / (6 + 4 + 5 + 9 + 6 + 9 + 5 + 4 + 6).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 645969492 and 645969501.

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, 5981146 + ... + 5981253.

It is an arithmetic number, because the mean of its divisors is an integer number (89718000).

Almost surely, 2^645969546 is an apocalyptic number.

645969546 is an abundant number, since it is smaller than the sum of its proper divisors (789518454).

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

645969546 is a wasteful number, since it uses less digits than its factorization.

645969546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11962410 (or 11962404 counting only the distinct ones).

The product of its digits is 6998400, while the sum is 54.

The square root of 645969546 is about 25415.9309489147. The cubic root of 645969546 is about 864.4449627402. Note that the first 3 decimals are identical.

The spelling of 645969546 in words is "six hundred forty-five million, nine hundred sixty-nine thousand, five hundred forty-six".