1640212981264 has 135 divisors (see below), whose sum is σ = 3784135012749. Its totient is φ = 687893880960.

The previous prime is 1640212981223. The next prime is 1640212981289. The reversal of 1640212981264 is 4621892120461.

The square root of 1640212981264 is 1280708.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 242635056400 + 1397577924864 = 492580^2 + 1182192^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 732563857 + ... + 732566095.

Almost surely, 2^{1640212981264} is an apocalyptic number.

1640212981264 is the 1280708-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1640212981264

1640212981264 is an abundant number, since it is smaller than the sum of its proper divisors (2143922031485).

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

1640212981264 is an equidigital number, since it uses as much as digits as its factorization.

1640212981264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4534 (or 2265 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 46.

The spelling of 1640212981264 in words is "one trillion, six hundred forty billion, two hundred twelve million, nine hundred eighty-one thousand, two hundred sixty-four".