664915039749 has 24 divisors (see below), whose sum is σ = 1017096132312. Its totient is φ = 417132979200.

The previous prime is 664915039741. The next prime is 664915039777. The reversal of 664915039749 is 947930519466.

664915039749 is a `hidden beast` number, since 6 + 6 + 491 + 50 + 3 + 97 + 4 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 153107864100 + 511807175649 = 391290^2 + 715407^2 .

It is not a de Polignac number, because 664915039749 - 2³ = 664915039741 is a prime.

It is a super-2 number, since 2×664915039749² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664915039741) 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, 584049 + ... + 1292649.

It is an arithmetic number, because the mean of its divisors is an integer number (42379005513).

Almost surely, 2^664915039749 is an apocalyptic number.

It is an amenable number.

664915039749 is a deficient number, since it is larger than the sum of its proper divisors (352181092563).

664915039749 is a wasteful number, since it uses less digits than its factorization.

664915039749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 714757 (or 714754 counting only the distinct ones).

The product of its (nonzero) digits is 44089920, while the sum is 63.

The spelling of 664915039749 in words is "six hundred sixty-four billion, nine hundred fifteen million, thirty-nine thousand, seven hundred forty-nine".