1660826121 has 4 divisors (see below), whose sum is σ = 2214434832. Its totient is φ = 1107217412.

The previous prime is 1660826051. The next prime is 1660826131. The reversal of 1660826121 is 1216280661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1216280661 = 3 ⋅405426887.

It is a cyclic number.

It is not a de Polignac number, because 1660826121 - 2¹⁸ = 1660563977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1660826131) 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, 276804351 + ... + 276804356.

It is an arithmetic number, because the mean of its divisors is an integer number (553608708).

Almost surely, 2^1660826121 is an apocalyptic number.

It is an amenable number.

1660826121 is a deficient number, since it is larger than the sum of its proper divisors (553608711).

1660826121 is an equidigital number, since it uses as much as digits as its factorization.

1660826121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553608710.

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 1660826121 is about 40753.2344851301. The cubic root of 1660826121 is about 1184.2445340527.

The spelling of 1660826121 in words is "one billion, six hundred sixty million, eight hundred twenty-six thousand, one hundred twenty-one".