1801531 has 2 divisors, whose sum is σ = 1801532. Its totient is φ = 1801530.

The previous prime is 1801529. The next prime is 1801549. The reversal of 1801531 is 1351081.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1801531 - 2¹ = 1801529 is a prime.

It is a super-2 number, since 2×1801531² = 6491027887922, which contains 22 as substring.

Together with 1801529, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1801499 and 1801508.

It is not a weakly prime, because it can be changed into another prime (1801931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 900765 + 900766.

It is an arithmetic number, because the mean of its divisors is an integer number (900766).

2^1801531 is an apocalyptic number.

1801531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1801531 is an equidigital number, since it uses as much as digits as its factorization.

1801531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 19.

The square root of 1801531 is about 1342.2112352383. The cubic root of 1801531 is about 121.6785184760.

It can be divided in two parts, 1801 and 531, that added together give a palindrome (2332).

The spelling of 1801531 in words is "one million, eight hundred one thousand, five hundred thirty-one".