1660604633021 has 4 divisors (see below), whose sum is σ = 1660607966652. Its totient is φ = 1660601299392.

The previous prime is 1660604632987. The next prime is 1660604633053. The reversal of 1660604633021 is 1203364060661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1345625520121 + 314979112900 = 1160011^2 + 561230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1660604633021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660604633621) 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, 752390 + ... + 1971623.

It is an arithmetic number, because the mean of its divisors is an integer number (415151991663).

Almost surely, 2^{1660604633021} is an apocalyptic number.

It is an amenable number.

1660604633021 is a deficient number, since it is larger than the sum of its proper divisors (3333631).

1660604633021 is an equidigital number, since it uses as much as digits as its factorization.

1660604633021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3333630.

The product of its (nonzero) digits is 93312, while the sum is 38.

Adding to 1660604633021 its reverse (1203364060661), we get a palindrome (2863968693682).

The spelling of 1660604633021 in words is "one trillion, six hundred sixty billion, six hundred four million, six hundred thirty-three thousand, twenty-one".