21838990577 has 4 divisors (see below), whose sum is σ = 22543474176. Its totient is φ = 21134506980.

The previous prime is 21838990573. The next prime is 21838990609. The reversal of 21838990577 is 77509983812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21838990577 - 2² = 21838990573 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21838990571) 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, 352241753 + ... + 352241814.

It is an arithmetic number, because the mean of its divisors is an integer number (5635868544).

Almost surely, 2^21838990577 is an apocalyptic number.

It is an amenable number.

21838990577 is a deficient number, since it is larger than the sum of its proper divisors (704483599).

21838990577 is an equidigital number, since it uses as much as digits as its factorization.

21838990577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704483598.

The product of its (nonzero) digits is 7620480, while the sum is 59.

The spelling of 21838990577 in words is "twenty-one billion, eight hundred thirty-eight million, nine hundred ninety thousand, five hundred seventy-seven".