1636645141 has 4 divisors (see below), whose sum is σ = 1667525292. Its totient is φ = 1605764992.

The previous prime is 1636645121. The next prime is 1636645147. The reversal of 1636645141 is 1415466361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1415466361 = 1583 ⋅894167.

It can be written as a sum of positive squares in 2 ways, for example, as 1192320900 + 444324241 = 34530^2 + 21079^2 .

It is a cyclic number.

It is not a de Polignac number, because 1636645141 - 2¹¹ = 1636643093 is a prime.

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 1636645141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1636645147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15439996 + ... + 15440101.

It is an arithmetic number, because the mean of its divisors is an integer number (416881323).

Almost surely, 2^1636645141 is an apocalyptic number.

It is an amenable number.

1636645141 is a deficient number, since it is larger than the sum of its proper divisors (30880151).

1636645141 is an equidigital number, since it uses as much as digits as its factorization.

1636645141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30880150.

The product of its digits is 51840, while the sum is 37.

The square root of 1636645141 is about 40455.4710885932. The cubic root of 1636645141 is about 1178.4690336424.

The spelling of 1636645141 in words is "one billion, six hundred thirty-six million, six hundred forty-five thousand, one hundred forty-one".