1640504995693 has 2 divisors, whose sum is σ = 1640504995694. Its totient is φ = 1640504995692.

The previous prime is 1640504995673. The next prime is 1640504995699. The reversal of 1640504995693 is 3965994050461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1640504995684 + 9 = 1280822^2 + 3^2 .

It is a cyclic number.

It is not a de Polignac number, because 1640504995693 - 2³⁷ = 1503066042221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1640504995699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820252497846 + 820252497847.

It is an arithmetic number, because the mean of its divisors is an integer number (820252497847).

Almost surely, 2^{1640504995693} is an apocalyptic number.

It is an amenable number.

1640504995693 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640504995693 is an equidigital number, since it uses as much as digits as its factorization.

1640504995693 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31492800, while the sum is 61.

The spelling of 1640504995693 in words is "one trillion, six hundred forty billion, five hundred four million, nine hundred ninety-five thousand, six hundred ninety-three".