1355999 has 2 divisors, whose sum is σ = 1356000. Its totient is φ = 1355998.

The previous prime is 1355989. The next prime is 1356007. The reversal of 1355999 is 9995531.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1355999 - 2⁴ = 1355983 is a prime.

It is a Chen prime.

It is a plaindrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1355989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 677999 + 678000.

It is an arithmetic number, because the mean of its divisors is an integer number (678000).

2^1355999 is an apocalyptic number.

1355999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1355999 is an equidigital number, since it uses as much as digits as its factorization.

1355999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54675, while the sum is 41.

The square root of 1355999 is about 1164.4737008623. The cubic root of 1355999 is about 110.6844105111.

It can be divided in two parts, 13559 and 99, that multiplied together give a triangular number (1342341 = T₁₆₃₈).

The spelling of 1355999 in words is "one million, three hundred fifty-five thousand, nine hundred ninety-nine".