1371661729 has 2 divisors, whose sum is σ = 1371661730. Its totient is φ = 1371661728.

The previous prime is 1371661727. The next prime is 1371661769. The reversal of 1371661729 is 9271661731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1030410000 + 341251729 = 32100^2 + 18473^2 .

It is a cyclic number.

It is not a de Polignac number, because 1371661729 - 2¹ = 1371661727 is a prime.

Together with 1371661727, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1371661723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 685830864 + 685830865.

It is an arithmetic number, because the mean of its divisors is an integer number (685830865).

Almost surely, 2^1371661729 is an apocalyptic number.

It is an amenable number.

1371661729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1371661729 is an equidigital number, since it uses as much as digits as its factorization.

1371661729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 95256, while the sum is 43.

The square root of 1371661729 is about 37035.9518441203. The cubic root of 1371661729 is about 1111.0894071468.

The spelling of 1371661729 in words is "one billion, three hundred seventy-one million, six hundred sixty-one thousand, seven hundred twenty-nine".