2161803557 has 4 divisors (see below), whose sum is σ = 2255795040. Its totient is φ = 2067812076.

The previous prime is 2161803533. The next prime is 2161803577. The reversal of 2161803557 is 7553081612.

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.

It is a cyclic number.

It is not a de Polignac number, because 2161803557 - 2²⁴ = 2145026341 is a prime.

It is a super-3 number, since 3×2161803557³ (a number of 29 digits) contains 333 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 2161803557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161803577) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46995707 + ... + 46995752.

It is an arithmetic number, because the mean of its divisors is an integer number (563948760).

Almost surely, 2^2161803557 is an apocalyptic number.

It is an amenable number.

2161803557 is a deficient number, since it is larger than the sum of its proper divisors (93991483).

2161803557 is an equidigital number, since it uses as much as digits as its factorization.

2161803557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93991482.

The product of its (nonzero) digits is 50400, while the sum is 38.

The square root of 2161803557 is about 46495.1992898192. The cubic root of 2161803557 is about 1293.0204959440.

The spelling of 2161803557 in words is "two billion, one hundred sixty-one million, eight hundred three thousand, five hundred fifty-seven".