21994794240 has 144 divisors (see below), whose sum is σ = 70942628736. Its totient is φ = 5807104000.

The previous prime is 21994794233. The next prime is 21994794271. The reversal of 21994794240 is 4249749912.

It is a super-3 number, since 3×21994794240³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 359485 + ... + 416195.

It is an arithmetic number, because the mean of its divisors is an integer number (492657144).

Almost surely, 2^21994794240 is an apocalyptic number.

21994794240 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 21994794240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35471314368).

21994794240 is an abundant number, since it is smaller than the sum of its proper divisors (48947834496).

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

21994794240 is a wasteful number, since it uses less digits than its factorization.

21994794240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56836 (or 56822 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 51.

The spelling of 21994794240 in words is "twenty-one billion, nine hundred ninety-four million, seven hundred ninety-four thousand, two hundred forty".