664734847 has 4 divisors (see below), whose sum is σ = 759696976. Its totient is φ = 569772720.

The previous prime is 664734841. The next prime is 664734853. The reversal of 664734847 is 748437466.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (664734841) and next prime (664734853).

It is a cyclic number.

It is not a de Polignac number, because 664734847 - 2¹⁵ = 664702079 is a prime.

It is a super-2 number, since 2×664734847² = 883744833632226818, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664734847.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664734841) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 47481054 + ... + 47481067.

It is an arithmetic number, because the mean of its divisors is an integer number (189924244).

Almost surely, 2^664734847 is an apocalyptic number.

664734847 is a deficient number, since it is larger than the sum of its proper divisors (94962129).

664734847 is an equidigital number, since it uses as much as digits as its factorization.

664734847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94962128.

The product of its digits is 2709504, while the sum is 49.

The square root of 664734847 is about 25782.4523077228. The cubic root of 664734847 is about 872.7358484259.

The spelling of 664734847 in words is "six hundred sixty-four million, seven hundred thirty-four thousand, eight hundred forty-seven".