1630618421 has 4 divisors (see below), whose sum is σ = 1670389644. Its totient is φ = 1590847200.

The previous prime is 1630618417. The next prime is 1630618433. The reversal of 1630618421 is 1248160361.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 333610225 + 1297008196 = 18265^2 + 36014^2 .

It is a cyclic number.

It is not a de Polignac number, because 1630618421 - 2² = 1630618417 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 (1630618471) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 19885550 + ... + 19885631.

It is an arithmetic number, because the mean of its divisors is an integer number (417597411).

Almost surely, 2^1630618421 is an apocalyptic number.

It is an amenable number.

1630618421 is a deficient number, since it is larger than the sum of its proper divisors (39771223).

1630618421 is an equidigital number, since it uses as much as digits as its factorization.

1630618421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39771222.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 1630618421 is about 40380.9165448235. The cubic root of 1630618421 is about 1177.0207379093.

Adding to 1630618421 its reverse (1248160361), we get a palindrome (2878778782).

The spelling of 1630618421 in words is "one billion, six hundred thirty million, six hundred eighteen thousand, four hundred twenty-one".