664145252 has 6 divisors (see below), whose sum is σ = 1162254198. Its totient is φ = 332072624.

The previous prime is 664145219. The next prime is 664145281. The reversal of 664145252 is 252541466.

It can be written as a sum of positive squares in only one way, i.e., 384787456 + 279357796 = 19616^2 + 16714^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83018153 + ... + 83018160.

It is an arithmetic number, because the mean of its divisors is an integer number (193709033).

Almost surely, 2^664145252 is an apocalyptic number.

It is an amenable number.

664145252 is a deficient number, since it is larger than the sum of its proper divisors (498108946).

664145252 is a wasteful number, since it uses less digits than its factorization.

664145252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166036317 (or 166036315 counting only the distinct ones).

The product of its digits is 57600, while the sum is 35.

The square root of 664145252 is about 25771.0157347358. The cubic root of 664145252 is about 872.4777440595.

The spelling of 664145252 in words is "six hundred sixty-four million, one hundred forty-five thousand, two hundred fifty-two".