1645164395690 has 16 divisors (see below), whose sum is σ = 2994568901640. Its totient is φ = 650671760640.

The previous prime is 1645164395597. The next prime is 1645164395713. The reversal of 1645164395690 is 965934615461.

It can be written as a sum of positive squares in 4 ways, for example, as 1295201048761 + 349963346929 = 1138069^2 + 591577^2 .

It is a super-2 number, since 2×1645164395690² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 924248771 + ... + 924250550.

Almost surely, 2^{1645164395690} is an apocalyptic number.

1645164395690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1645164395690 is a deficient number, since it is larger than the sum of its proper divisors (1349404505950).

1645164395690 is a wasteful number, since it uses less digits than its factorization.

1645164395690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1848499417.

The product of its (nonzero) digits is 20995200, while the sum is 59.

The spelling of 1645164395690 in words is "one trillion, six hundred forty-five billion, one hundred sixty-four million, three hundred ninety-five thousand, six hundred ninety".