21258443833344 has 135 divisors (see below), whose sum is σ = 61416523060347. Its totient is φ = 7085557776384.

The previous prime is 21258443833337. The next prime is 21258443833349. The reversal of 21258443833344 is 44333834485212.

It is a happy number.

The square root of 21258443833344 is 4610688.

It is a perfect power (a square), and thus also a powerful number.

21258443833344 is a `hidden beast` number, since 2 + 1 + 2 + 58 + 443 + 83 + 33 + 44 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21258443833349) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1770498189 + ... + 1770510195.

Almost surely, 2^{21258443833344} is an apocalyptic number.

21258443833344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

21258443833344 is the 4610688-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21258443833344

21258443833344 is an abundant number, since it is smaller than the sum of its proper divisors (40158079227003).

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

21258443833344 is an frugal number, since it uses more digits than its factorization.

21258443833344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24048 (or 12012 counting only the distinct ones).

The product of its digits is 26542080, while the sum is 54.

The spelling of 21258443833344 in words is "twenty-one trillion, two hundred fifty-eight billion, four hundred forty-three million, eight hundred thirty-three thousand, three hundred forty-four".