1721211016 has 128 divisors (see below), whose sum is σ = 3981312000. Its totient is φ = 681811200.

The previous prime is 1721211013. The next prime is 1721211059. The reversal of 1721211016 is 6101121271.

It is not an unprimeable number, because it can be changed into a prime (1721211013) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9011481 + ... + 9011671.

It is an arithmetic number, because the mean of its divisors is an integer number (31104000).

Almost surely, 2^1721211016 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1721211016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1990656000).

1721211016 is an abundant number, since it is smaller than the sum of its proper divisors (2260100984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1721211016 is a wasteful number, since it uses less digits than its factorization.

1721211016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443 (or 439 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 22.

The square root of 1721211016 is about 41487.4802319929. The cubic root of 1721211016 is about 1198.4264133488.

Adding to 1721211016 its reverse (6101121271), we get a palindrome (7822332287).

The spelling of 1721211016 in words is "one billion, seven hundred twenty-one million, two hundred eleven thousand, sixteen".