1640440264 has 8 divisors (see below), whose sum is σ = 3075825510. Its totient is φ = 820220128.

The previous prime is 1640440253. The next prime is 1640440267. The reversal of 1640440264 is 4620440461.

It can be written as a sum of positive squares in only one way, i.e., 1623284100 + 17156164 = 40290^2 + 4142^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (1640440267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102527509 + ... + 102527524.

Almost surely, 2^1640440264 is an apocalyptic number.

It is an amenable number.

1640440264 is a deficient number, since it is larger than the sum of its proper divisors (1435385246).

1640440264 is a wasteful number, since it uses less digits than its factorization.

1640440264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205055039 (or 205055035 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 31.

The square root of 1640440264 is about 40502.3488701581. The cubic root of 1640440264 is about 1179.3792253329.

The spelling of 1640440264 in words is "one billion, six hundred forty million, four hundred forty thousand, two hundred sixty-four".