21430468920 has 128 divisors (see below), whose sum is σ = 73617891840. Its totient is φ = 4888926720.

The previous prime is 21430468909. The next prime is 21430468921. The reversal of 21430468920 is 2986403412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21430468921) 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 31 ways as a sum of consecutive naturals, for example, 414930 + ... + 463710.

It is an arithmetic number, because the mean of its divisors is an integer number (575139780).

Almost surely, 2^21430468920 is an apocalyptic number.

21430468920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21430468920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36808945920).

21430468920 is an abundant number, since it is smaller than the sum of its proper divisors (52187422920).

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

21430468920 is a wasteful number, since it uses less digits than its factorization.

21430468920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49325 (or 49321 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 39.

The spelling of 21430468920 in words is "twenty-one billion, four hundred thirty million, four hundred sixty-eight thousand, nine hundred twenty".