664661026 has 16 divisors (see below), whose sum is σ = 1005530400. Its totient is φ = 329491008.

The previous prime is 664660999. The next prime is 664661029. The reversal of 664661026 is 620166466.

It is not an unprimeable number, because it can be changed into a prime (664661029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 311130 + ... + 313258.

It is an arithmetic number, because the mean of its divisors is an integer number (62845650).

Almost surely, 2^664661026 is an apocalyptic number.

664661026 is a deficient number, since it is larger than the sum of its proper divisors (340869374).

664661026 is a wasteful number, since it uses less digits than its factorization.

664661026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3393.

The product of its (nonzero) digits is 62208, while the sum is 37.

The square root of 664661026 is about 25781.0206547375. The cubic root of 664661026 is about 872.7035404972.

The spelling of 664661026 in words is "six hundred sixty-four million, six hundred sixty-one thousand, twenty-six".