1631632729 has 2 divisors, whose sum is σ = 1631632730. Its totient is φ = 1631632728.

The previous prime is 1631632727. The next prime is 1631632789. The reversal of 1631632729 is 9272361361.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1287159129 + 344473600 = 35877^2 + 18560^2 .

It is a cyclic number.

It is not a de Polignac number, because 1631632729 - 2¹ = 1631632727 is a prime.

Together with 1631632727, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1631632691 and 1631632700.

It is not a weakly prime, because it can be changed into another prime (1631632727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 815816364 + 815816365.

It is an arithmetic number, because the mean of its divisors is an integer number (815816365).

Almost surely, 2^1631632729 is an apocalyptic number.

It is an amenable number.

1631632729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1631632729 is an equidigital number, since it uses as much as digits as its factorization.

1631632729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 40.

The square root of 1631632729 is about 40393.4738416987. The cubic root of 1631632729 is about 1177.2647381974.

It can be divided in two parts, 1631632 and 729, that added together give a palindrome (1632361).

The spelling of 1631632729 in words is "one billion, six hundred thirty-one million, six hundred thirty-two thousand, seven hundred twenty-nine".