21790813827 has 8 divisors (see below), whose sum is σ = 29452424464. Its totient is φ = 14328206208.

The previous prime is 21790813813. The next prime is 21790813831. The reversal of 21790813827 is 72831809712.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21790813827 - 2⁶ = 21790813763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21790813427) 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 7 ways as a sum of consecutive naturals, for example, 49750498 + ... + 49750935.

It is an arithmetic number, because the mean of its divisors is an integer number (3681553058).

Almost surely, 2^21790813827 is an apocalyptic number.

21790813827 is a deficient number, since it is larger than the sum of its proper divisors (7661610637).

21790813827 is an equidigital number, since it uses as much as digits as its factorization.

21790813827 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99501509.

The product of its (nonzero) digits is 338688, while the sum is 48.

The spelling of 21790813827 in words is "twenty-one billion, seven hundred ninety million, eight hundred thirteen thousand, eight hundred twenty-seven".