645454545 has 16 divisors (see below), whose sum is σ = 1037363712. Its totient is φ = 342696960.

The previous prime is 645454519. The next prime is 645454549. The reversal of 645454545 is 545454546.

It is not a de Polignac number, because 645454545 - 2⁷ = 645454417 is a prime.

It is a super-2 number, since 2×645454545² = 833223139322314050, which contains 22 as substring.

645454545 is a modest number, since divided by 454545 gives 645 as remainder.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 645454497 and 645454506.

It is not an unprimeable number, because it can be changed into a prime (645454549) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 93136 + ... + 99825.

It is an arithmetic number, because the mean of its divisors is an integer number (64835232).

Almost surely, 2^645454545 is an apocalyptic number.

It is an amenable number.

645454545 is a deficient number, since it is larger than the sum of its proper divisors (391909167).

645454545 is a wasteful number, since it uses less digits than its factorization.

645454545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193192.

The product of its digits is 960000, while the sum is 42.

The square root of 645454545 is about 25405.7974682945. The cubic root of 645454545 is about 864.2151746203.

Subtracting from 645454545 its reverse (545454546), we obtain a palindrome (99999999).

The spelling of 645454545 in words is "six hundred forty-five million, four hundred fifty-four thousand, five hundred forty-five".