1375821 has 12 divisors (see below), whose sum is σ = 2021760. Its totient is φ = 901320.

The previous prime is 1375819. The next prime is 1375823. The reversal of 1375821 is 1285731.

It is an interprime number because it is at equal distance from previous prime (1375819) and next prime (1375823).

It is not a de Polignac number, because 1375821 - 2¹ = 1375819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1375823) 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 11 ways as a sum of consecutive naturals, for example, 765 + ... + 1826.

It is an arithmetic number, because the mean of its divisors is an integer number (168480).

2^1375821 is an apocalyptic number.

It is an amenable number.

1375821 is a deficient number, since it is larger than the sum of its proper divisors (645939).

1375821 is a wasteful number, since it uses less digits than its factorization.

1375821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2656 (or 2653 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 1375821 is about 1172.9539632910. The cubic root of 1375821 is about 111.2211320966.

The spelling of 1375821 in words is "one million, three hundred seventy-five thousand, eight hundred twenty-one".