2164542521 has 4 divisors (see below), whose sum is σ = 2167456512. Its totient is φ = 2161628532.

The previous prime is 2164542511. The next prime is 2164542539. The reversal of 2164542521 is 1252454612.

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 2164542521 - 2¹⁰ = 2164541497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2164542511) 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, 1455881 + ... + 1457366.

It is an arithmetic number, because the mean of its divisors is an integer number (541864128).

Almost surely, 2^2164542521 is an apocalyptic number.

It is an amenable number.

2164542521 is a deficient number, since it is larger than the sum of its proper divisors (2913991).

2164542521 is an equidigital number, since it uses as much as digits as its factorization.

2164542521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2913990.

The product of its digits is 19200, while the sum is 32.

The square root of 2164542521 is about 46524.6442329224. The cubic root of 2164542521 is about 1293.5663429435.

The spelling of 2164542521 in words is "two billion, one hundred sixty-four million, five hundred forty-two thousand, five hundred twenty-one".