21755367379 has 4 divisors (see below), whose sum is σ = 22218247584. Its totient is φ = 21292487176.

The previous prime is 21755367371. The next prime is 21755367401. The reversal of 21755367379 is 97376355712.

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 21755367379 - 2³ = 21755367371 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21755367371) 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, 231440032 + ... + 231440125.

It is an arithmetic number, because the mean of its divisors is an integer number (5554561896).

Almost surely, 2^21755367379 is an apocalyptic number.

21755367379 is a deficient number, since it is larger than the sum of its proper divisors (462880205).

21755367379 is an equidigital number, since it uses as much as digits as its factorization.

21755367379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462880204.

The product of its digits is 8334900, while the sum is 55.

The spelling of 21755367379 in words is "twenty-one billion, seven hundred fifty-five million, three hundred sixty-seven thousand, three hundred seventy-nine".