1722799021 has 4 divisors (see below), whose sum is σ = 1730388672. Its totient is φ = 1715209372.

The previous prime is 1722799019. The next prime is 1722799033. The reversal of 1722799021 is 1209972271.

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 1722799021 - 2¹ = 1722799019 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 (1722799621) 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, 3794485 + ... + 3794938.

It is an arithmetic number, because the mean of its divisors is an integer number (432597168).

Almost surely, 2^1722799021 is an apocalyptic number.

It is an amenable number.

1722799021 is a deficient number, since it is larger than the sum of its proper divisors (7589651).

1722799021 is an equidigital number, since it uses as much as digits as its factorization.

1722799021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7589650.

The product of its (nonzero) digits is 31752, while the sum is 40.

The square root of 1722799021 is about 41506.6141837659. The cubic root of 1722799021 is about 1198.7948597786.

The spelling of 1722799021 in words is "one billion, seven hundred twenty-two million, seven hundred ninety-nine thousand, twenty-one".