1665542163746 has 4 divisors (see below), whose sum is σ = 2498313245622. Its totient is φ = 832771081872.

The previous prime is 1665542163697. The next prime is 1665542163749. The reversal of 1665542163746 is 6473612455661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1131489601225 + 534052562521 = 1063715^2 + 730789^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1665542163691 and 1665542163700.

It is not an unprimeable number, because it can be changed into a prime (1665542163749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 416385540935 + ... + 416385540938.

Almost surely, 2^{1665542163746} is an apocalyptic number.

1665542163746 is a deficient number, since it is larger than the sum of its proper divisors (832771081876).

1665542163746 is an equidigital number, since it uses as much as digits as its factorization.

1665542163746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832771081875.

The product of its digits is 21772800, while the sum is 56.

The spelling of 1665542163746 in words is "one trillion, six hundred sixty-five billion, five hundred forty-two million, one hundred sixty-three thousand, seven hundred forty-six".