1636319380969 has 27 divisors (see below), whose sum is σ = 2061304405317. Its totient is φ = 1294578177984.

The previous prime is 1636319380967. The next prime is 1636319380973. The reversal of 1636319380969 is 9690839136361.

The square root of 1636319380969 is 1279187.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1153933569369 + 482385811600 = 1074213^2 + 694540^2 .

It is not a de Polignac number, because 1636319380969 - 2¹ = 1636319380967 is a prime.

It is a super-2 number, since 2×1636319380969² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1636319380969.

It is not an unprimeable number, because it can be changed into a prime (1636319380967) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 116398989 + ... + 116413045.

Almost surely, 2^{1636319380969} is an apocalyptic number.

1636319380969 is the 1279187-th square number.

1636319380969 is the 639594-th centered octagonal number.

It is an amenable number.

1636319380969 is a deficient number, since it is larger than the sum of its proper divisors (424985024348).

1636319380969 is an frugal number, since it uses more digits than its factorization.

1636319380969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28154 (or 14077 counting only the distinct ones).

The product of its (nonzero) digits is 34012224, while the sum is 64.

Multiplying 1636319380969 by its sum of digits (64), we get a square (104724440382016 = 10233496²).

The spelling of 1636319380969 in words is "one trillion, six hundred thirty-six billion, three hundred nineteen million, three hundred eighty thousand, nine hundred sixty-nine".