21389019960 has 384 divisors, whose sum is σ = 81290280960. Its totient is φ = 4406814720.

The previous prime is 21389019959. The next prime is 21389020007. The reversal of 21389019960 is 6991098312.

It is a hoax number, since the sum of its digits (48) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 12907452 + ... + 12909108.

It is an arithmetic number, because the mean of its divisors is an integer number (211693440).

Almost surely, 2^21389019960 is an apocalyptic number.

21389019960 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 21389019960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40645140480).

21389019960 is an abundant number, since it is smaller than the sum of its proper divisors (59901261000).

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

21389019960 is a wasteful number, since it uses less digits than its factorization.

21389019960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1827 (or 1812 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 48.

The spelling of 21389019960 in words is "twenty-one billion, three hundred eighty-nine million, nineteen thousand, nine hundred sixty".