1375681 has 2 divisors, whose sum is σ = 1375682. Its totient is φ = 1375680.

The previous prime is 1375679. The next prime is 1375709. The reversal of 1375681 is 1865731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1343281 + 32400 = 1159^2 + 180^2 .

It is a cyclic number.

It is not a de Polignac number, because 1375681 - 2¹ = 1375679 is a prime.

It is a super-2 number, since 2×1375681² = 3784996427522, which contains 22 as substring.

Together with 1375679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1375601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 687840 + 687841.

It is an arithmetic number, because the mean of its divisors is an integer number (687841).

2^1375681 is an apocalyptic number.

It is an amenable number.

1375681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1375681 is an equidigital number, since it uses as much as digits as its factorization.

1375681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 31.

The square root of 1375681 is about 1172.8942833862. The cubic root of 1375681 is about 111.2173594433.

The spelling of 1375681 in words is "one million, three hundred seventy-five thousand, six hundred eighty-one".