213160021 has 6 divisors (see below), whose sum is σ = 222831350. Its totient is φ = 203891688.

The previous prime is 213159983. The next prime is 213160033. The reversal of 213160021 is 120061312.

It can be written as a sum of positive squares in only one way, i.e., 202037796 + 11122225 = 14214^2 + 3335^2 .

It is not a de Polignac number, because 213160021 - 2⁹ = 213159509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 213159977 and 213160004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213160721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 200946 + ... + 202003.

Almost surely, 2^213160021 is an apocalyptic number.

It is an amenable number.

213160021 is a deficient number, since it is larger than the sum of its proper divisors (9671329).

213160021 is an equidigital number, since it uses as much as digits as its factorization.

213160021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402995 (or 402972 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 213160021 is about 14600.0007191781. Note that the first 3 decimals coincide. The cubic root of 213160021 is about 597.3587801380.

The spelling of 213160021 in words is "two hundred thirteen million, one hundred sixty thousand, twenty-one".