711216021 has 4 divisors (see below), whose sum is σ = 948288032. Its totient is φ = 474144012.

The previous prime is 711216013. The next prime is 711216049. The reversal of 711216021 is 120612117.

It is a happy number.

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: 120612117 = 3 ⋅40204039.

It is not a de Polignac number, because 711216021 - 2³ = 711216013 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 (711216221) 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, 118536001 + ... + 118536006.

It is an arithmetic number, because the mean of its divisors is an integer number (237072008).

Almost surely, 2^711216021 is an apocalyptic number.

It is an amenable number.

711216021 is a deficient number, since it is larger than the sum of its proper divisors (237072011).

711216021 is a wasteful number, since it uses less digits than its factorization.

711216021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237072010.

The product of its (nonzero) digits is 168, while the sum is 21.

The square root of 711216021 is about 26668.6336545388. The cubic root of 711216021 is about 892.6211584531.

Adding to 711216021 its reverse (120612117), we get a palindrome (831828138).

The spelling of 711216021 in words is "seven hundred eleven million, two hundred sixteen thousand, twenty-one".