1630323721 has 8 divisors (see below), whose sum is σ = 1756153224. Its totient is φ = 1504554240.

The previous prime is 1630323707. The next prime is 1630323731. The reversal of 1630323721 is 1273230361.

It can be written as a sum of positive squares in 4 ways, for example, as 19184400 + 1611139321 = 4380^2 + 40139^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1630323721 - 2¹³ = 1630315529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1630323721.

It is not an unprimeable number, because it can be changed into a prime (1630323731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52785 + ... + 77761.

It is an arithmetic number, because the mean of its divisors is an integer number (219519153).

Almost surely, 2^1630323721 is an apocalyptic number.

It is an amenable number.

1630323721 is a deficient number, since it is larger than the sum of its proper divisors (125829503).

1630323721 is a wasteful number, since it uses less digits than its factorization.

1630323721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30011.

The product of its (nonzero) digits is 4536, while the sum is 28.

The square root of 1630323721 is about 40377.2673790587. The cubic root of 1630323721 is about 1176.9498263857.

It can be divided in two parts, 163032 and 3721, that added together give a triangular number (166753 = T₅₇₇).

The spelling of 1630323721 in words is "one billion, six hundred thirty million, three hundred twenty-three thousand, seven hundred twenty-one".