21211219979 has 8 divisors (see below), whose sum is σ = 21435827952. Its totient is φ = 20986898400.

The previous prime is 21211219973. The next prime is 21211220021. The reversal of 21211219979 is 97991211212.

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

It is a cyclic number.

It is not a de Polignac number, because 21211219979 - 2⁴ = 21211219963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21211219973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78977 + ... + 220589.

It is an arithmetic number, because the mean of its divisors is an integer number (2679478494).

Almost surely, 2^21211219979 is an apocalyptic number.

21211219979 is a deficient number, since it is larger than the sum of its proper divisors (224607973).

21211219979 is a wasteful number, since it uses less digits than its factorization.

21211219979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143197.

The product of its digits is 40824, while the sum is 44.

The spelling of 21211219979 in words is "twenty-one billion, two hundred eleven million, two hundred nineteen thousand, nine hundred seventy-nine".