664452540 has 36 divisors (see below), whose sum is σ = 2015506584. Its totient is φ = 177187296.

The previous prime is 664452539. The next prime is 664452557. The reversal of 664452540 is 45254466.

664452540 is a `hidden beast` number, since 6 + 64 + 4 + 52 + 540 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 664452495 and 664452504.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1845522 + ... + 1845881.

It is an arithmetic number, because the mean of its divisors is an integer number (55986294).

Almost surely, 2^664452540 is an apocalyptic number.

664452540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

664452540 is an abundant number, since it is smaller than the sum of its proper divisors (1351054044).

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

664452540 is a wasteful number, since it uses less digits than its factorization.

664452540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3691418 (or 3691413 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 36.

The square root of 664452540 is about 25776.9769367938. The cubic root of 664452540 is about 872.6122832044.

The spelling of 664452540 in words is "six hundred sixty-four million, four hundred fifty-two thousand, five hundred forty".