1565381 has 2 divisors, whose sum is σ = 1565382. Its totient is φ = 1565380.

The previous prime is 1565351. The next prime is 1565383. The reversal of 1565381 is 1835651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1136356 + 429025 = 1066^2 + 655^2 .

It is an emirp because it is prime and its reverse (1835651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1565381 - 2¹⁴ = 1548997 is a prime.

It is a super-2 number, since 2×1565381² = 4900835350322, which contains 22 as substring.

Together with 1565383, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1565383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 782690 + 782691.

It is an arithmetic number, because the mean of its divisors is an integer number (782691).

2^1565381 is an apocalyptic number.

It is an amenable number.

1565381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1565381 is an equidigital number, since it uses as much as digits as its factorization.

1565381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3600, while the sum is 29.

The square root of 1565381 is about 1251.1518692789. The cubic root of 1565381 is about 116.1109966108.

The spelling of 1565381 in words is "one million, five hundred sixty-five thousand, three hundred eighty-one".