21489597879 has 8 divisors (see below), whose sum is σ = 28668201072. Its totient is φ = 14318696640.

The previous prime is 21489597859. The next prime is 21489597967. The reversal of 21489597879 is 97879598412.

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

It is not a de Polignac number, because 21489597879 - 2¹⁶ = 21489532343 is a prime.

It is a super-2 number, since 2×21489597879² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21489597809) 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, 1918974 + ... + 1930139.

It is an arithmetic number, because the mean of its divisors is an integer number (3583525134).

Almost surely, 2^21489597879 is an apocalyptic number.

21489597879 is a deficient number, since it is larger than the sum of its proper divisors (7178603193).

21489597879 is a wasteful number, since it uses less digits than its factorization.

21489597879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3850977.

The product of its digits is 91445760, while the sum is 69.

The spelling of 21489597879 in words is "twenty-one billion, four hundred eighty-nine million, five hundred ninety-seven thousand, eight hundred seventy-nine".