21979354458 has 16 divisors (see below), whose sum is σ = 44033603040. Its totient is φ = 7313969136.

The previous prime is 21979354421. The next prime is 21979354469. The reversal of 21979354458 is 85445397912.

It is a junction number, because it is equal to n+sod(n) for n = 21979354398 and 21979354407.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3116773 + ... + 3123816.

It is an arithmetic number, because the mean of its divisors is an integer number (2752100190).

Almost surely, 2^21979354458 is an apocalyptic number.

21979354458 is an abundant number, since it is smaller than the sum of its proper divisors (22054248582).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21979354458 is a wasteful number, since it uses less digits than its factorization.

21979354458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6241181.

The product of its digits is 10886400, while the sum is 57.

The spelling of 21979354458 in words is "twenty-one billion, nine hundred seventy-nine million, three hundred fifty-four thousand, four hundred fifty-eight".