664530993 has 48 divisors (see below), whose sum is σ = 1173251520. Its totient is φ = 370440000.

The previous prime is 664530959. The next prime is 664531031. The reversal of 664530993 is 399035466.

It is a happy number.

It is not a de Polignac number, because 664530993 - 2¹⁶ = 664465457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664530913) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 48118 + ... + 60368.

It is an arithmetic number, because the mean of its divisors is an integer number (24442740).

Almost surely, 2^664530993 is an apocalyptic number.

664530993 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

It is an amenable number.

664530993 is a deficient number, since it is larger than the sum of its proper divisors (508720527).

664530993 is a wasteful number, since it uses less digits than its factorization.

664530993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12315 (or 12302 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 45.

The square root of 664530993 is about 25778.4986568264. The cubic root of 664530993 is about 872.6466254401.

The spelling of 664530993 in words is "six hundred sixty-four million, five hundred thirty thousand, nine hundred ninety-three".