21835390079 has 4 divisors (see below), whose sum is σ = 21883170384. Its totient is φ = 21787609776.

The previous prime is 21835390069. The next prime is 21835390091. The reversal of 21835390079 is 97009353812.

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 21835390079 - 2¹² = 21835385983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21835390069) 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, 23889467 + ... + 23890380.

It is an arithmetic number, because the mean of its divisors is an integer number (5470792596).

Almost surely, 2^21835390079 is an apocalyptic number.

21835390079 is a deficient number, since it is larger than the sum of its proper divisors (47780305).

21835390079 is an equidigital number, since it uses as much as digits as its factorization.

21835390079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47780304.

The product of its (nonzero) digits is 408240, while the sum is 47.

The spelling of 21835390079 in words is "twenty-one billion, eight hundred thirty-five million, three hundred ninety thousand, seventy-nine".