645826455 has 24 divisors (see below), whose sum is σ = 1120962960. Its totient is φ = 343969920.

The previous prime is 645826439. The next prime is 645826457. The reversal of 645826455 is 554628546.

645826455 is a `hidden beast` number, since 6 + 4 + 582 + 64 + 5 + 5 = 666.

It is not a de Polignac number, because 645826455 - 2⁴ = 645826439 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 645826455.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645826457) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24816 + ... + 43674.

It is an arithmetic number, because the mean of its divisors is an integer number (46706790).

Almost surely, 2^645826455 is an apocalyptic number.

645826455 is a deficient number, since it is larger than the sum of its proper divisors (475136505).

645826455 is a wasteful number, since it uses less digits than its factorization.

645826455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19631 (or 19628 counting only the distinct ones).

The product of its digits is 1152000, while the sum is 45.

The square root of 645826455 is about 25413.1158066066. The cubic root of 645826455 is about 864.3811292724.

The spelling of 645826455 in words is "six hundred forty-five million, eight hundred twenty-six thousand, four hundred fifty-five".