52181999 has 4 divisors (see below), whose sum is σ = 54928440. Its totient is φ = 49435560.

The previous prime is 52181957. The next prime is 52182029. The reversal of 52181999 is 99918125.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 52181999 - 2⁸ = 52181743 is a prime.

It is a super-2 number, since 2×52181999² = 5445922039272002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (52181929) 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, 1373192 + ... + 1373229.

It is an arithmetic number, because the mean of its divisors is an integer number (13732110).

Almost surely, 2^52181999 is an apocalyptic number.

52181999 is a deficient number, since it is larger than the sum of its proper divisors (2746441).

52181999 is a wasteful number, since it uses less digits than its factorization.

52181999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2746440.

The product of its digits is 58320, while the sum is 44.

The square root of 52181999 is about 7223.7108884562. The cubic root of 52181999 is about 373.6860658789.

The spelling of 52181999 in words is "fifty-two million, one hundred eighty-one thousand, nine hundred ninety-nine".