1721721466 has 8 divisors (see below), whose sum is σ = 2590730100. Its totient is φ = 858144768.

The previous prime is 1721721433. The next prime is 1721721467. The reversal of 1721721466 is 6641271271.

It can be written as a sum of positive squares in 2 ways, for example, as 1195707241 + 526014225 = 34579^2 + 22935^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1721721467) 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, 1357191 + ... + 1358458.

Almost surely, 2^1721721466 is an apocalyptic number.

1721721466 is a deficient number, since it is larger than the sum of its proper divisors (869008634).

1721721466 is a wasteful number, since it uses less digits than its factorization.

1721721466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2715968.

The product of its digits is 28224, while the sum is 37.

The square root of 1721721466 is about 41493.6316318541. The cubic root of 1721721466 is about 1198.5448718631.

It can be divided in two parts, 17217 and 21466, that added together give a palindrome (38683).

The spelling of 1721721466 in words is "one billion, seven hundred twenty-one million, seven hundred twenty-one thousand, four hundred sixty-six".