664561007536734 has 144 divisors (see below), whose sum is σ = 1827250703746416. Its totient is φ = 172611721094400.

The previous prime is 664561007536669. The next prime is 664561007536763. The reversal of 664561007536734 is 437635700165466.

664561007536734 is a `hidden beast` number, since 6 + 6 + 4 + 5 + 61 + 0 + 0 + 7 + 536 + 7 + 34 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1457216154 + ... + 1457672130.

It is an arithmetic number, because the mean of its divisors is an integer number (12689240998239).

Almost surely, 2^{664561007536734} is an apocalyptic number.

664561007536734 is an abundant number, since it is smaller than the sum of its proper divisors (1162689696209682).

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

664561007536734 is a wasteful number, since it uses less digits than its factorization.

664561007536734 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606231 (or 606221 counting only the distinct ones).

The product of its (nonzero) digits is 228614400, while the sum is 63.

The spelling of 664561007536734 in words is "six hundred sixty-four trillion, five hundred sixty-one billion, seven million, five hundred thirty-six thousand, seven hundred thirty-four".