21394683144 has 128 divisors (see below), whose sum is σ = 60034252800. Its totient is φ = 7059286080.

The previous prime is 21394683137. The next prime is 21394683169. The reversal of 21394683144 is 44138649312.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21394683144.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21588489 + ... + 21589479.

It is an arithmetic number, because the mean of its divisors is an integer number (469017600).

Almost surely, 2^21394683144 is an apocalyptic number.

21394683144 is a gapful number since it is divisible by the number (24) 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 21394683144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30017126400).

21394683144 is an abundant number, since it is smaller than the sum of its proper divisors (38639569656).

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

21394683144 is a wasteful number, since it uses less digits than its factorization.

21394683144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1920 (or 1910 counting only the distinct ones).

The product of its digits is 497664, while the sum is 45.

The spelling of 21394683144 in words is "twenty-one billion, three hundred ninety-four million, six hundred eighty-three thousand, one hundred forty-four".