645456801 has 16 divisors (see below), whose sum is σ = 939814848. Its totient is φ = 390782400.

The previous prime is 645456793. The next prime is 645456827. The reversal of 645456801 is 108654546.

It is a happy number.

645456801 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 645456801 - 2³ = 645456793 is a prime.

It is a super-2 number, since 2×645456801² = 833228963914307202, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 645456801.

It is not an unprimeable number, because it can be changed into a prime (645456701) 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, 24115 + ... + 43271.

It is an arithmetic number, because the mean of its divisors is an integer number (58738428).

Almost surely, 2^645456801 is an apocalyptic number.

It is an amenable number.

645456801 is a deficient number, since it is larger than the sum of its proper divisors (294358047).

645456801 is a wasteful number, since it uses less digits than its factorization.

645456801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20192.

The product of its (nonzero) digits is 115200, while the sum is 39.

The square root of 645456801 is about 25405.8418675705. The cubic root of 645456801 is about 864.2161814907.

It can be divided in two parts, 645 and 456801, that added together give a triangular number (457446 = T₉₅₆).

The spelling of 645456801 in words is "six hundred forty-five million, four hundred fifty-six thousand, eight hundred one".