1801799381 has 4 divisors (see below), whose sum is σ = 1802480172. Its totient is φ = 1801118592.

The previous prime is 1801799341. The next prime is 1801799399. The reversal of 1801799381 is 1839971081.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1246443025 + 555356356 = 35305^2 + 23566^2 .

It is a cyclic number.

It is not a de Polignac number, because 1801799381 - 2¹⁸ = 1801537237 is a prime.

It is a super-2 number, since 2×1801799381² = 6492962018743966322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1801799341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 336410 + ... + 341723.

It is an arithmetic number, because the mean of its divisors is an integer number (450620043).

Almost surely, 2^1801799381 is an apocalyptic number.

It is an amenable number.

1801799381 is a deficient number, since it is larger than the sum of its proper divisors (680791).

1801799381 is an equidigital number, since it uses as much as digits as its factorization.

1801799381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680790.

The product of its (nonzero) digits is 108864, while the sum is 47.

The square root of 1801799381 is about 42447.6074826368. The cubic root of 1801799381 is about 1216.8456048155.

The spelling of 1801799381 in words is "one billion, eight hundred one million, seven hundred ninety-nine thousand, three hundred eighty-one".