2156017819 has 4 divisors (see below), whose sum is σ = 2162531800. Its totient is φ = 2149503840.

The previous prime is 2156017771. The next prime is 2156017849. The reversal of 2156017819 is 9187106512.

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 2156017819 - 2⁹ = 2156017307 is a prime.

It is a super-2 number, since 2×2156017819² = 9296825671691033522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2156017849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3256494 + ... + 3257155.

It is an arithmetic number, because the mean of its divisors is an integer number (540632950).

Almost surely, 2^2156017819 is an apocalyptic number.

2156017819 is a deficient number, since it is larger than the sum of its proper divisors (6513981).

2156017819 is an equidigital number, since it uses as much as digits as its factorization.

2156017819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6513980.

The product of its (nonzero) digits is 30240, while the sum is 40.

The square root of 2156017819 is about 46432.9389442452. The cubic root of 2156017819 is about 1291.8659411860.

The spelling of 2156017819 in words is "two billion, one hundred fifty-six million, seventeen thousand, eight hundred nineteen".