56981819 has 4 divisors (see below), whose sum is σ = 56997096. Its totient is φ = 56966544.

The previous prime is 56981791. The next prime is 56981849. The reversal of 56981819 is 91818965.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 56981819 - 2⁸ = 56981563 is a prime.

It is a super-2 number, since 2×56981819² = 6493855393097522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56981849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2072 + ... + 10874.

It is an arithmetic number, because the mean of its divisors is an integer number (14249274).

Almost surely, 2^56981819 is an apocalyptic number.

56981819 is a deficient number, since it is larger than the sum of its proper divisors (15277).

56981819 is an equidigital number, since it uses as much as digits as its factorization.

56981819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15276.

The product of its digits is 155520, while the sum is 47.

The square root of 56981819 is about 7548.6302731025. The cubic root of 56981819 is about 384.8091908823.

The spelling of 56981819 in words is "fifty-six million, nine hundred eighty-one thousand, eight hundred nineteen".