1721306245 has 8 divisors (see below), whose sum is σ = 2072919960. Its totient is φ = 1372143360.

The previous prime is 1721306227. The next prime is 1721306261. The reversal of 1721306245 is 5426031271.

It can be written as a sum of positive squares in 4 ways, for example, as 702356004 + 1018950241 = 26502^2 + 31921^2 .

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

It is not a de Polignac number, because 1721306245 - 2²⁹ = 1184435333 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 611160 + ... + 613969.

It is an arithmetic number, because the mean of its divisors is an integer number (259114995).

Almost surely, 2^1721306245 is an apocalyptic number.

It is an amenable number.

1721306245 is a deficient number, since it is larger than the sum of its proper divisors (351613715).

1721306245 is a wasteful number, since it uses less digits than its factorization.

1721306245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1225415.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 1721306245 is about 41488.6278997028. The cubic root of 1721306245 is about 1198.4485146180.

The spelling of 1721306245 in words is "one billion, seven hundred twenty-one million, three hundred six thousand, two hundred forty-five".