21420244104 has 32 divisors (see below), whose sum is σ = 61200697920. Its totient is φ = 6120069696.

The previous prime is 21420244063. The next prime is 21420244147. The reversal of 21420244104 is 40144202412.

It is a Harshad number since it is a multiple of its sum of digits (24).

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, 63750559 + ... + 63750894.

It is an arithmetic number, because the mean of its divisors is an integer number (1912521810).

Almost surely, 2^21420244104 is an apocalyptic number.

21420244104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21420244104 is an abundant number, since it is smaller than the sum of its proper divisors (39780453816).

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

21420244104 is a wasteful number, since it uses less digits than its factorization.

21420244104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127501469 (or 127501465 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 24.

Adding to 21420244104 its reverse (40144202412), we get a palindrome (61564446516).

The spelling of 21420244104 in words is "twenty-one billion, four hundred twenty million, two hundred forty-four thousand, one hundred four".